Java Factorial factorial(int n)

Here you can find the source of factorial(int n)

Description

basically a lookup-function for n!

License

Apache License

Parameter

Parameter Description
n a parameter

Declaration

public static double factorial(int n) 

Method Source Code

//package com.java2s;
/* /*from   w  ww . j a  va2 s.co m*/
 * Copyright 2016 Lutz Fischer <l.fischer@ed.ac.uk>.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

public class Main {
    private static final double[] factorials = { /* 0 */ 1d
            /* 1 */ , 1d
            /* 2 */ , 2d
            /* 3 */ , 6d
            /* 4 */ , 24d
            /* 5 */ , 120d
            /* 6 */ , 720d
            /* 7 */ , 5040d
            /* 8 */ , 40320d
            /* 9 */ , 362880d
            /* 10 */ , 3628800d
            /* 11 */ , 39916800d
            /* 12 */ , 479001600d
            /* 13 */ , 6227020800d
            /* 14 */ , 87178291200d
            /* 15 */ , 1307674368000d
            /* 16 */ , 20922789888000d
            /* 17 */ , 355687428096000d
            /* 18 */ , 6402373705728000d
            /* 19 */ , 121645100408832000d
            /* 20 */ , 2432902008176640000d
            /* 21 */ , 51090942171709440000d
            /* 22 */ , 1124000727777607680000d
            /* 23 */ , 25852016738884976640000d
            /* 24 */ , 620448401733239439360000d
            /* 25 */ , 15511210043330985984000000d
            /* 26 */ , 403291461126605635584000000d
            /* 27 */ , 10888869450418352160768000000d
            /* 28 */ , 304888344611713860501504000000d
            /* 29 */ , 8841761993739701954543616000000d
            /* 30 */ , 265252859812191058636308480000000d
            /* 31 */ , 8222838654177922817725562880000000d
            /* 32 */ , 263130836933693530167218012160000000d
            /* 33 */ , 8683317618811886495518194401280000000d
            /* 34 */ , 295232799039604140847618609643520000000d
            /* 35 */ , 10333147966386144929666651337523200000000d
            /* 36 */ , 371993326789901217467999448150835200000000d
            /* 37 */ , 13763753091226345046315979581580902400000000d
            /* 38 */ , 523022617466601111760007224100074291200000000d
            /* 39 */ , 20397882081197443358640281739902897356800000000d
            /* 40 */ , 815915283247897734345611269596115894272000000000d
            /* 41 */ , 33452526613163807108170062053440751665152000000000d
            /* 42 */ , 1405006117752879898543142606244511569936384000000000d
            /* 43 */ , 60415263063373835637355132068513997507264512000000000d
            /* 44 */ , 2658271574788448768043625811014615890319638528000000000d
            /* 45 */ , 119622220865480194561963161495657715064383733760000000000d
            /* 46 */ , 5502622159812088949850305428800254892961651752960000000000d
            /* 47 */ , 258623241511168180642964355153611979969197632389120000000000d
            /* 48 */ , 12413915592536072670862289047373375038521486354677760000000000d
            /* 49 */ , 608281864034267560872252163321295376887552831379210240000000000d
            /* 50 */ , 30414093201713378043612608166064768844377641568960512000000000000d
            /* 51 */ , 1551118753287382280224243016469303211063259720016986112000000000000d
            /* 52 */ , 80658175170943878571660636856403766975289505440883277824000000000000d
            /* 53 */ , 4274883284060025564298013753389399649690343788366813724672000000000000d
            /* 54 */ , 230843697339241380472092742683027581083278564571807941132288000000000000d
            /* 55 */ , 12696403353658275925965100847566516959580321051449436762275840000000000000d
            /* 56 */ , 710998587804863451854045647463724949736497978881168458687447040000000000000d
            /* 57 */ , 40526919504877216755680601905432322134980384796226602145184481280000000000000d
            /* 58 */ , 2350561331282878571829474910515074683828862318181142924420699914240000000000000d
            /* 59 */ , 138683118545689835737939019720389406345902876772687432540821294940160000000000000d
            /* 60 */ , 8320987112741390144276341183223364380754172606361245952449277696409600000000000000d
            /* 61 */ , 507580213877224798800856812176625227226004528988036003099405939480985600000000000000d
            /* 62 */ , 31469973260387937525653122354950764088012280797258232192163168247821107200000000000000d
            /* 63 */ , 1982608315404440064116146708361898137544773690227268628106279599612729753600000000000000d
            /* 64 */ , 126886932185884164103433389335161480802865516174545192198801894375214704230400000000000000d
            /* 65 */ , 8247650592082470666723170306785496252186258551345437492922123134388955774976000000000000000d
            /* 66 */ ,
            544344939077443064003729240247842752644293064388798874532860126869671081148416000000000000000d
            /* 67 */ ,
            36471110918188685288249859096605464427167635314049524593701628500267962436943872000000000000000d
            /* 68 */ ,
            2480035542436830599600990418569171581047399201355367672371710738018221445712183296000000000000000d
            /* 69 */ ,
            171122452428141311372468338881272839092270544893520369393648040923257279754140647424000000000000000d
            /* 70 */ ,
            11978571669969891796072783721689098736458938142546425857555362864628009582789845319680000000000000000d
            /* 71 */ ,
            850478588567862317521167644239926010288584608120796235886430763388588680378079017697280000000000000000d
            /* 72 */ ,
            61234458376886086861524070385274672740778091784697328983823014963978384987221689274204160000000000000000d
            /* 73 */ ,
            4470115461512684340891257138125051110076800700282905015819080092370422104067183317016903680000000000000000d
            /* 74 */ ,
            330788544151938641225953028221253782145683251820934971170611926835411235700971565459250872320000000000000000d
            /* 75 */ ,
            24809140811395398091946477116594033660926243886570122837795894512655842677572867409443815424000000000000000000d
            /* 76 */ ,
            1885494701666050254987932260861146558230394535379329335672487982961844043495537923117729972224000000000000000000d
            /* 77 */ ,
            145183092028285869634070784086308284983740379224208358846781574688061991349156420080065207861248000000000000000000d
            /* 78 */ ,
            11324281178206297831457521158732046228731749579488251990048962825668835325234200766245086213177344000000000000000000d
            /* 79 */ ,
            894618213078297528685144171539831652069808216779571907213868063227837990693501860533361810841010176000000000000000000d
            /* 80 */ ,
            71569457046263802294811533723186532165584657342365752577109445058227039255480148842668944867280814080000000000000000000d
            /* 81 */ ,
            5797126020747367985879734231578109105412357244731625958745865049716390179693892056256184534249745940480000000000000000000d
            /* 82 */ ,
            475364333701284174842138206989404946643813294067993328617160934076743994734899148613007131808479167119360000000000000000000d
            /* 83 */ ,
            39455239697206586511897471180120610571436503407643446275224357528369751562996629334879591940103770870906880000000000000000000d
            /* 84 */ ,
            3314240134565353266999387579130131288000666286242049487118846032383059131291716864129885722968716753156177920000000000000000000d
            /* 85 */ ,
            281710411438055027694947944226061159480056634330574206405101912752560026159795933451040286452340924018275123200000000000000000000d
            /* 86 */ ,
            24227095383672732381765523203441259715284870552429381750838764496720162249742450276789464634901319465571660595200000000000000000000d
            /* 87 */ ,
            2107757298379527717213600518699389595229783738061356212322972511214654115727593174080683423236414793504734471782400000000000000000000d
            /* 88 */ ,
            185482642257398439114796845645546284380220968949399346684421580986889562184028199319100141244804501828416633516851200000000000000000000d
            /* 89 */ ,
            16507955160908461081216919262453619309839666236496541854913520707833171034378509739399912570787600662729080382999756800000000000000000000d
            /* 90 */ ,
            1485715964481761497309522733620825737885569961284688766942216863704985393094065876545992131370884059645617234469978112000000000000000000000d
            /* 91 */ ,
            135200152767840296255166568759495142147586866476906677791741734597153670771559994765685283954750449427751168336768008192000000000000000000000d
            /* 92 */ ,
            12438414054641307255475324325873553077577991715875414356840239582938137710983519518443046123837041347353107486982656753664000000000000000000000d
            /* 93 */ ,
            1156772507081641574759205162306240436214753229576413535186142281213246807121467315215203289516844845303838996289387078090752000000000000000000000d
            /* 94 */ ,
            108736615665674308027365285256786601004186803580182872307497374434045199869417927630229109214583415458560865651202385340530688000000000000000000000d
            /* 95 */ ,
            10329978488239059262599702099394727095397746340117372869212250571234293987594703124871765375385424468563282236864226607350415360000000000000000000000d
            /* 96 */ ,
            991677934870949689209571401541893801158183648651267795444376054838492222809091499987689476037000748982075094738965754305639874560000000000000000000000d
            /* 97 */ ,
            96192759682482119853328425949563698712343813919172976158104477319333745612481875498805879175589072651261284189679678167647067832320000000000000000000000d
            /* 98 */ ,
            9426890448883247745626185743057242473809693764078951663494238777294707070023223798882976159207729119823605850588608460429412647567360000000000000000000000d
            /* 99 */ ,
            933262154439441526816992388562667004907159682643816214685929638952175999932299156089414639761565182862536979208272237582511852109168640000000000000000000000d
            /* 100 */ ,
            93326215443944152681699238856266700490715968264381621468592963895217599993229915608941463976156518286253697920827223758251185210916864000000000000000000000000d
            /* 101 */ ,
            9425947759838359420851623124482936749562312794702543768327889353416977599316221476503087861591808346911623490003549599583369706302603264000000000000000000000000d
            /* 102 */ ,
            961446671503512660926865558697259548455355905059659464369444714048531715130254590603314961882364451384985595980362059157503710042865532928000000000000000000000000d
            /* 103 */ ,
            99029007164861804075467152545817733490901658221144924830052805546998766658416222832141441073883538492653516385977292093222882134415149891584000000000000000000000000d
            /* 104 */ ,
            10299016745145627623848583864765044283053772454999072182325491776887871732475287174542709871683888003235965704141638377695179741979175588724736000000000000000000000000d
            /* 105 */ ,
            1081396758240290900504101305800329649720646107774902579144176636573226531909905153326984536526808240339776398934872029657993872907813436816097280000000000000000000000000d
            /* 106 */ ,
            114628056373470835453434738414834942870388487424139673389282723476762012382449946252660360871841673476016298287096435143747350528228224302506311680000000000000000000000000d
            /* 107 */ ,
            12265202031961379393517517010387338887131568154382945052653251412013535324922144249034658613287059061933743916719318560380966506520420000368175349760000000000000000000000000d
            /* 108 */ ,
            1324641819451828974499891837121832599810209360673358065686551152497461815091591578895743130235002378688844343005686404521144382704205360039762937774080000000000000000000000000d
            /* 109 */ ,
            144385958320249358220488210246279753379312820313396029159834075622223337844983482099636001195615259277084033387619818092804737714758384244334160217374720000000000000000000000000d
            /* 110 */ ,
            15882455415227429404253703127090772871724410234473563207581748318444567162948183030959960131517678520479243672638179990208521148623422266876757623911219200000000000000000000000000d
            /* 111 */ ,
            1762952551090244663872161047107075788761409536026565516041574063347346955087248316436555574598462315773196047662837978913145847497199871623320096254145331200000000000000000000000000d
            /* 112 */ ,
            197450685722107402353682037275992488341277868034975337796656295094902858969771811440894224355027779366597957338237853638272334919686385621811850780464277094400000000000000000000000000d
            /* 113 */ ,
            22311927486598136465966070212187151182564399087952213171022161345724023063584214692821047352118139068425569179220877461124773845924561575264739138192463311667200000000000000000000000000d
            /* 114 */ ,
            2543559733472187557120132004189335234812341496026552301496526393412538629248600474981599398141467853800514886431180030568224218435400019580180261753940817530060800000000000000000000000000d
            /* 115 */ ,
            292509369349301569068815180481773552003419272043053514672100535242441942363589054622883930786268803187059211939585703515345785120071002251720730101703194015956992000000000000000000000000000d
            /* 116 */ ,
            33931086844518982011982560935885732032396635556994207701963662088123265314176330336254535971207181169698868584991941607780111073928236261199604691797570505851011072000000000000000000000000000d
            /* 117 */ ,
            3969937160808720895401959629498630647790406360168322301129748464310422041758630649341780708631240196854767624444057168110272995649603642560353748940315749184568295424000000000000000000000000000d
            /* 118 */ ,
            468452584975429065657431236280838416439267950499862031533310318788629800927518416622330123618486343228862579684398745837012213486653229822121742374957258403779058860032000000000000000000000000000d
            /* 119 */ ,
            55745857612076058813234317117419771556272886109483581752463927935846946310374691578057284710599874844234646982443450754604453404911734348832487342619913750049708004343808000000000000000000000000000d
            /* 120 */ ,
            6689502913449127057588118054090372586752746333138029810295671352301633557244962989366874165271984981308157637893214090552534408589408121859898481114389650005964960521256960000000000000000000000000000d
            /* 121 */ ,
            809429852527344373968162284544935082997082306309701607045776233628497660426640521713391773997910182738287074185078904956856663439318382745047716214841147650721760223072092160000000000000000000000000000d
            /* 122 */ ,
            98750442008336013624115798714482080125644041369783596059584700502676714572050143649033796427745042294071023050579626404736512939596842694895821378210620013388054747214795243520000000000000000000000000000d
            /* 123 */ ,
            12146304367025329675766243241881295855454217088483382315328918161829235892362167668831156960612640202170735835221294047782591091570411651472186029519906261646730733907419814952960000000000000000000000000000d
            /* 124 */ ,
            1506141741511140879795014161993280686076322918971939407100785852066825250652908790935063463115967385069171243567440461925041295354731044782551067660468376444194611004520057054167040000000000000000000000000000d
            /* 125 */ ,
            188267717688892609974376770249160085759540364871492425887598231508353156331613598866882932889495923133646405445930057740630161919341380597818883457558547055524326375565007131770880000000000000000000000000000000d
            /* 126 */ ,
            23721732428800468856771473051394170805702085973808045661837377170052497697783313457227249544076486314839447086187187275319400401837013955325179315652376928996065123321190898603130880000000000000000000000000000000d
            /* 127 */ ,
            3012660018457659544809977077527059692324164918673621799053346900596667207618480809067860692097713761984609779945772783965563851033300772326297773087851869982500270661791244122597621760000000000000000000000000000000d
            /* 128 */ ,
            385620482362580421735677065923463640617493109590223590278828403276373402575165543560686168588507361534030051833058916347592172932262498857766114955245039357760034644709279247692495585280000000000000000000000000000000d
            /* 129 */ ,
            49745042224772874403902341504126809639656611137138843145968864022652168932196355119328515747917449637889876686464600208839390308261862352651828829226610077151044469167497022952331930501120000000000000000000000000000000d
            /* 130 */ ,
            6466855489220473672507304395536485253155359447828049608975952322944781961185526165512707047229268452925683969240398027149120740074042105844737747799459310029635780991774612983803150965145600000000000000000000000000000000d
            /* 131 */ ,
            847158069087882051098456875815279568163352087665474498775849754305766436915303927682164623187034167333264599970492141556534816949699515865660644961729169613882287309922474300878212776434073600000000000000000000000000000000d
            /* 132 */ ,
            111824865119600430744996307607616902997562475571842633838412167568361169672820118454045730260688510087990927196104962685462595837360336094267205134948250389032461924909766607715924086489297715200000000000000000000000000000000d
            /* 133 */ ,
            14872707060906857289084508911813048098675809251055070300508818286592035566485075754388082124671571841702793317081960037166525246368924700537538282948117301741317436012998958826217903503076596121600000000000000000000000000000000d
            /* 134 */ ,
            1992942746161518876737324194182948445222558439641379420268181650403332765909000151088003004705990626788174304488982644980314383013435909872030129915047718433336536425741860482713199069412263880294400000000000000000000000000000000d
            /* 135 */ ,
            269047270731805048359538766214698040105045389351586221736204522804449923397715020396880405635308734616403531106012657072342441706813847832724067538531441988500432417475151165166281874370655623839744000000000000000000000000000000000d
            /* 136 */ ,
            36590428819525486576897272205198933454286172951815726156123815101405189582089242773975735166401987907830880230417721361838572072126683305250473185240276110436058808776620558462614334914409164842205184000000000000000000000000000000000d
            /* 137 */ ,
            5012888748274991661034926292112253883237205694398754483388962668892510972746226260034675717797072343372830591567227826571884373881355612819314826377917827129740056802397016509378163883274055583382110208000000000000000000000000000000000d
            /* 138 */ ,
            691778647261948849222819828311491035886734385827028118707676848307166514238979223884785249055995983385450621636277440066920043595627074569065446040152660143904127838730788278294186615891819670506731208704000000000000000000000000000000000d
            /* 139 */ ,
            96157231969410890041971956135297253988256079629956908500367081914696145479218112119985149618783441690577636407442564169301886059792163365100096999581219760002673769583579570682891939608962934200435638009856000000000000000000000000000000000d
            /* 140 */ ,
            13462012475717524605876073858941615558355851148193967190051391468057460367090535696797920946629681836680869097041958983702264048370902871114013579941370766400374327741701139895604871545254810788060989321379840000000000000000000000000000000000d
            /* 141 */ ,
            1898143759076170969428526414110767793728175011895349373797246196996101911759765533248506853474785138972002542682916216702019230820297304827075914771733278062452780211579860725280286887880928321116599494314557440000000000000000000000000000000000d
            /* 142 */ ,
            269536413788816277658850750803729026709400851689139611079208959973446471469886705721287973193419489734024361060974102771686730776482217285444779897586125484868294790044340222989800738079091821598557128192667156480000000000000000000000000000000000d
            /* 143 */ ,
            38543707171800727705215657364933250819444321791546964384326881276202845420193798918144180166658987031965483631719296696351202501036957071818603525354815944336166154976340651887541505545310130488593669331551403376640000000000000000000000000000000000d
            /* 144 */ ,
            5550293832739304789551054660550388117999982337982762871343070903773209740507907044212761943998894132603029642967578724274573160149321818341878907651093495984407926316593053871805976798524658790357488383743402086236160000000000000000000000000000000000d
            /* 145 */ ,
            804792605747199194484902925779806277109997439007500616344745281047115412373646521410850481879839649227439298230298915019813108221651663659572441609408556917739149315905992811411866635786075524601835815642793302504243200000000000000000000000000000000000d
            /* 146 */ ,
            117499720439091082394795827163851716458059626095095089986332811032878850206552392125984170354456588787206137541623641592892713800361142894297576474973649309989915800122274950466132528824767026591868029083847822165619507200000000000000000000000000000000000d
            /* 147 */ ,
            17272458904546389112034986593086202319334765035978978227990923221833190980363201642519673042105118551719302218618675314155228928653088005461743741821126448568517622617974417718521481737240752909004600275325629858346067558400000000000000000000000000000000000d
            /* 148 */ ,
            2556323917872865588581178015776757943261545225324888777742656636831312265093753843092911610231557545654456728355563946494973881440657024808338073789526714388140608147460213822341179297111631430532680840748193219035217998643200000000000000000000000000000000000d
            /* 149 */ ,
            380892263763056972698595524350736933545970238573408427883655838887865527498969322620843829924502074302514052524979028027751108334657896696442372994639480443832950613971571859528835715269633083149369445271480789636247481797836800000000000000000000000000000000000d
            /* 150 */ ,
            57133839564458545904789328652610540031895535786011264182548375833179829124845398393126574488675311145377107878746854204162666250198684504466355949195922066574942592095735778929325357290444962472405416790722118445437122269675520000000000000000000000000000000000000d
            /* 151 */ ,
            8627209774233240431623188626544191544816225903687700891564804750810154197851655157362112747789971982951943289690774984828562603780001360174419748328584232052816331406456102618328128950857189333333217935399039885261005462721003520000000000000000000000000000000000000d
            /* 152 */ ,
            1311335885683452545606724671234717114812066337360530535517850322123143438073451583919041137664075741408695380032997797693941515774560206746511801745944803272028082373781327597985875600530292778666649126180654062559672830333592535040000000000000000000000000000000000000d
            /* 153 */ ,
            200634390509568239477828874698911718566246149616161171934231099284840946025238092339613294062603588435530393145048663047173051913507711632216305667129554900620296603188543122491838966881134795135997316305640071571629943041039657861120000000000000000000000000000000000000d
            /* 154 */ ,
            30897696138473508879585646703632404659201907040888820477871589289865505687886666220300447285640952619071680544337494109264649994680187591361311072737951454695525676891035640863743200899694758450943586711068571022031011228320107310612480000000000000000000000000000000000000d
            /* 155 */ ,
            4789142901463393876335775239063022722176295591337767174070096339929153381622433264146569329274347655956110484372311586936020749175429076661003216274382475477806479918110524333880196139452687559896255940215628508414806740389616633144934400000000000000000000000000000000000000d
            /* 156 */ ,
            747106292628289444708380937293831544659502112248691679154935029028947927533099589206864815366798234329153235562080607562019236871366935959116501738803666174537810867225241796085310597754619259343815926673638047312709851500780194770609766400000000000000000000000000000000000000d
            /* 157 */ ,
            117295687942641442819215807155131552511541831623044593627324799557544824622696635505477776012587322789677057983246655387237020188804608945581290772992175589402436306154362961985393763847475223716979100487761173428095446685622490578985733324800000000000000000000000000000000000000d
            /* 158 */ ,
            18532718694937347965436097530510785296823609396441045793117318330092082290386068409865488609988797000768975161352971551183449189831128213401843942132763743125584936372389347993692214687901085347282697877066265401639080576328353511479745865318400000000000000000000000000000000000000d
            /* 159 */ ,
            2946702272495038326504339507351214862194953894034126281105653614484641084171384877168612688988218723122267050655122476638168421183149385930893186799109435156968004883209906330997062135376272570217948962453536198860613811636208208325279592585625600000000000000000000000000000000000000d
            /* 160 */ ,
            471472363599206132240694321176194377951192623045460204976904578317542573467421580346978030238114995699562728104819596262106947389303901748942909887857509625114880781313585012959529941660203611234871833992565791817698209861793313332044734813700096000000000000000000000000000000000000000d
            /* 161 */ ,
            75907050539472187290751785709367294850142012310319093001281637109124354328254874435863462868336514307629599224875954998199218529677928181579808491945059049643495805791487187086484320607292781408814365272803092482649411787748723446459202305005715456000000000000000000000000000000000000000d
            /* 162 */ ,
            12296942187394494341101789284917501765723005994271693066207625211678145401177289658609880984670515317835995074429904709708273401807824365415928975695099566042246320538220924308010459938381430588227927174194100982189204709615293198326390773410925903872000000000000000000000000000000000000000d
            /* 163 */ ,
            2004401576545302577599591653441552787812849977066285969791842909503537700391898214353410600501293996807267197132074467682448564494675371562796423038301229264886150247730010662205704969956173185881152129393638460096840367667292791327201696065980922331136000000000000000000000000000000000000000d
            /* 164 */ ,
            328721858553429622726333031164414657201307396238870899045862237158580182864271307153959338482212215476391820329660212699921564577126760936298613378281401599441328640627721748601735615072812402484508949220556707455881820297436017777661078154820871262306304000000000000000000000000000000000000000d
            /* 165 */ ,
            54239106661315887749844950142128418438215720379413698342567269131165730172604765680403290849565015553604650354393935095487058155225915554489271207416431263907819225703574088519286376487014046409943976621391856730220500349076942933314077895545443758280540160000000000000000000000000000000000000000d
            /* 166 */ ,
            9003691705778437366474261723593317460743809582982673924866166675773511208652391102946946281027792581898371958829393225850851653767501982045219020431127589808697991466793298694201538496844331704050700119151048217216603057946772526930136930660543663874569666560000000000000000000000000000000000000000d
            /* 167 */ ,
            1503616514864999040201201707840084015944216200358106545452649834854176371844949314192140028931641361177028117124508668717092226179172831001551576411998307498052564574954480881931656928973003394576466919898225052275172710677111011997332867420310791867053134315520000000000000000000000000000000000000000d
            /* 168 */ ,
            252607574497319838753801886917134114678628321660161899636045172255501630469951484784279524860515748677740723676917456344471493998101035608260664837215715659672830848592352788164518364067464570288846442542901808782229015393754650015551921726612213033664926565007360000000000000000000000000000000000000000d
            /* 169 */ ,
            42690680090047052749392518888995665380688186360567361038491634111179775549421800928543239701427161526538182301399050122215682485679075017796052357489455946484708413412107621199803603527401512378815048789750405684196703601544535852628274771797464002689372589486243840000000000000000000000000000000000000000d
            /* 170 */ ,
            7257415615307998967396728211129263114716991681296451376543577798900561843401706157852350749242617459511490991237838520776666022565442753025328900773207510902400430280058295603966612599658257104398558294257568966313439612262571094946806711205568880457193340212661452800000000000000000000000000000000000000000d };
    /**
     * the highest pre-calculated factorial - this is also the last factorial that does not exceed the limits of a double.
     * 170!=7.257415615307999E+306.
     */
    public static final int LAST_DOUBLE_FACTORIAL = factorials.length;

    /**
     * basically a lookup-function for n!
     * @param n
     * @return 
     */
    public static double factorial(int n) {
        // to speed up calculation all factorials that result in valid double values 
        // are precalculated. 170! is the last factorial still representable by a double.
        if (n < 0) {
            throw new IllegalArgumentException("factorial can only handle n >= 0");
        }

        if (n > LAST_DOUBLE_FACTORIAL) {
            throw new ArithmeticException(
                    "Can't calculate a factorial for n larger then " + factorials.length + " within doubles.");
        } else {
            // do a simple lookup
            return factorials[n]; // take the shortcut :)
        }
    }
}

Related

  1. factorial(int n)
  2. factorial(int n)
  3. factorial(int n)
  4. factorial(int n)
  5. factorial(int n)
  6. factorial(int n)
  7. factorial(int n)
  8. factorial(int n)
  9. factorial(int n)