Dear Simon, I send you Euler's constant to 1000000 digits. The algorithm used is the one presented in the paper of McMillan and Brent [1] (the second variant) accelerated by binary splitting [2], [3]. This calculation verified the previous 500000-digits record to 499927 digits. Using the 500000-digit value of gamma and a program by H.J.J. te Riele, CWI Amsterdam [4], I was also able to compute 470006 partial quotients of the continued fraction of gamma. Computing the 470006-th convergent results in the following [5] Theorem: If Euler's constant is a rational number P/Q, for integers P, Q then |Q| > 10^242080 * Acknowledgements * The latest calculation would have been possible without the help and motivation from H.J.J. te Riele, Richard Brent and my colleague Bruno Haible. Best Thomas Papanikolaou References: [1] R. P. Brent and E. M. McMillan, Some new algorithms for high-precision computation of Euler's constant, Math. Comp. 34 (1980) 305-312. [2] Bruno Haible, Thomas Papanikolaou, Fast multiprecision evaluation of series of rational numbers, Technical Report No. TI-7/97, 18.03.1997. Available via http://www.informatik.th-darmstadt.de/TI/Veroeffentlichung/TR/Welcome.html [3] Jonathan M. Borwein and Peter B. Borwein, Pi and the AGM, Wiley, 1987. [4] Richard P. Brent, Alfred J. van der Poorten and Herman J.J. te Riele, A comparative study of algorithms for computing continued fractions of algebraic numbers, pp. 37-49 in: H. Cohen (editor), Algorithmic Number Theory: Second International Symposium, ANTS-II, Talence, France, 18-23.05.1996, Springer, Berlin etc., 1996. [5] Thomas Papanikolaou, Entwurf und Entwicklung einer objektorientierten Bibliothek f\"ur algorithmische Zahlentheorie, PhD Thesis, to appear. [6] Steve Finch, http://pauillac.inria.fr/algo/bsolve/euler/euler.html ------------------------------------------------------------------------------- Euler's constant to 1000000 digits computed on Mars 24, 1997 on a Sun Sparc Ultra machine with 167 Mhz and 256 MB RAM in 42 hours 27 hsec. The algorithm was implemented using the LiDIA library for computational number theory and it will be part of the multiprecision floating-point arithmetic of the package in release 1.4. LiDIA is available from ftp.informatik.th-darmstadt.de:/pub/TI/systems/LiDIA http://www.informatik.th-darmstadt.de/TI/LiDIA LiDIA's kernel used Bruno Haible's CLN package, which is available via anonymous FTP from ma2s2.mathematik.uni-karlsruhe.de:/pub/gnu/cln.tar.z This package contains the first implementation of a binary splitting device for rational series. ------------------------------------------------------------------------------ Here is the output of the program: Calculating Euler's constant to 1000000 decimals Time required: 42 hour 27 hsec Euler = 0.5772156649015328606065120900824024310421593359399235988057672348848677267776\ 646709369470632917467495146314472498070824809605040144865428362241739976449235\ 362535003337429373377376739427925952582470949160087352039481656708532331517766\ 115286211995015079847937450857057400299213547861466940296043254215190587755352\ 673313992540129674205137541395491116851028079842348775872050384310939973613725\ 530608893312676001724795378367592713515772261027349291394079843010341777177808\ 815495706610750101619166334015227893586796549725203621287922655595366962817638\ 879272680132431010476505963703947394957638906572967929601009015125195950922243\ 501409349871228247949747195646976318506676129063811051824197444867836380861749\ 455169892792301877391072945781554316005002182844096053772434203285478367015177\ 394398700302370339518328690001558193988042707411542227819716523011073565833967\ 348717650491941812300040654693142999297779569303100503086303418569803231083691\ 640025892970890985486825777364288253954925873629596133298574739302373438847070\ 370284412920166417850248733379080562754998434590761643167103146710722370021810\ 745044418664759134803669025532458625442225345181387912434573501361297782278288\ 148945909863846006293169471887149587525492366493520473243641097268276160877595\ 088095126208404544477992299157248292516251278427659657083214610298214617951957\ 959095922704208989627971255363217948873764210660607065982561990102880756125199\ 137511678217643619057058440783573501580056077457934213144988500786415171615194\ 565706170432450750081687052307890937046143066848179164968425491504967243121837\ 838753564894950868454102340601622508515583867234944187880440940770106883795111\ 307872023426395226920971608856908382511378712836820491178925944784861991185293\ 910293099059255266917274468920443869711147174571574573203935209122316085086827\ 558890109451681181016874975470969366671210206304827165895049327314860874940207\ 006742590918248759621373842311442653135029230317517225722162832488381124589574\ 386239870375766285513033143929995401853134141586212788648076110030152119657800\ 681177737635016818389733896639868957932991456388644310370608078174489957958324\ 579418962026049841043922507860460362527726022919682995860988339013787171422691\ 788381952984456079160519727973604759102510995779133515791772251502549293246325\ 028747677948421584050759929040185576459901862692677643726605711768133655908815\ 548107470000623363725288949554636971433012007913085552639595497823023144039149\ 740494746825947320846185246058776694882879530104063491722921858008706770690427\ 926743284446968514971825678095841654491851457533196406331199373821573450874988\ 325560888873528019019155089688554682592454445277281730573010806061770113637731\ 824629246600812771621018677446849595142817901451119489342288344825307531187018\ 609761224623176749775564124619838564014841235871772495542248201615176579940806\ 296834242890572594739269638633838743805471319676429268372490760875073785283702\ 304686503490512034227217436689792848629729088926789777032624623912261888765300\ 577862743606094443603928097708133836934235508583941126709218734414512187803276\ 150509478055466300586845563152454605315113252818891079231491311032344302450933\ 450003076558648742229717700331784539150566940159988492916091140029486902088485\ 381697009551566347055445221764035862939828658131238701325358800625686626926997\ 767737730683226900916085104515002261071802554659284938949277595897540761559933\ 782648241979506418681437881718508854080367996314239540091964388750078900000627\ 997942809886372992591977765040409922037940427616817837156686530669398309165243\ 227059553041766736640116792959012930537449718308004275848635083808042466735093\ 559832324116969214860649892763624432958854873789701489713343538448002890466650\ 902845376896223983048814062730540879591189670574938544324786914808533770264067\ 758081275458731117636478787430739206642011251352727499617545053085582356683068\ 322917676677041035231535032510124656386156706449847132695969330167866138333333\ 441657900605867497103646895174569597181553764078377650184278345991842015995431\ 449047725552306147670165993416390660912054005322158902091340802782251533852899\ 511665452245869185993671220132150144801424230986254604488672569343148870491593\ 044640189164502022405495386291847586293077889350643771596606909604681243702305\ 465703160679992587166675247219409777980186362625633582526279422393254860132693\ 530701388937436923842878938512764740856548650281563067740442203064403756826309\ 102917514572234441050369317711452170888907446416048688701083862311426128441425\ 960956370400619200579335034155242624026206465693543061258526583452192121497771\ 878069586608516334922104836737994592594340379560002192785418379417760203365594\ 673078879838084816314678241492354649148876683368407492893865281863048589820354\ 818624383848175997635849075180791480634943916284705482200754945348986133827235\ 730922190030740096800337666844932505567654937530318112516410552492384077645149\ 842395762012781552322944928854557853820248918942441857095919558208100071578384\ 039627479985817880888865716830699436060735990421068511427913169699596792300828\ 988156097538338059109360341252998656790389568795673455083362907823862638563490\ 747319275278740166557531190111543470018186256971261120126852923129937161403906\ 965112224816615082353643982396620532633322248505191593682690715004315589871802\ 783353845448309107249498057880961717996337167036554180041464667538719586948483\ 331543583330641935929487420951478832347748481418149776871694413640056645156936\ 116524161555734141935424721373067468333849054426626038372788217552709930958141\ 026136979500786465876771608630804460749802801576962675913897794772214337515470\ 829345879123898433055067223474969984942486706721502569273529585065869588997486\ 535562186958043997125168976654169862653862891977542187721939605817001104236414\ 158780810386172101557551923711160049880682291618097732421958328974869227183979\ 190467716542668138893379296036815457939611339621922245430151580631743708405608\ 536416031384982969518566952612822123716939368130321296561939718710207098007948\ 833910197535104307441823448833331796978277332091143324514305086573457500687391\ 475470777577559918467118308583660159437193718449039061770232536567977596744475\ 747511584195746700997345002454428406585024508585646392791246119879093693072019\ 804029303603738838430742162821201635386466226097198958436799430572030149638050\ 832232365825557724534237187737439818333306454662906993311125973721950274646899\ 065457155440303917835419756434315739034883866750542742161831050060550464223545\ 708427393549359051762717479299472398908632970101905610107742690926475235740304\ 630159243442464900834188630859320685522507790910195858895314328799817570981916\ 829315940453005632543314488517357302698256937253469964013440871580108145287865\ 790408663637945071108505104241797691911292615132010316363498086606948624407800\ 668400671696221463718114777268341846646364242734053003138077349611998146861768\ 585463120816316479893796426373835661893831371098328956490521148813402974238886\ 863154313297876579912545424333856347200268129048994955042698088213026726358153\ 248067538790323057421040330149788786752377860705468861472100992632942510887801\ 970284117922402591091466584809257857192786282147667074087863519714256292427867\ 028407703241437569931883243331559002433304769111009247979118006286202213707800\ 621725732904735994398883139279927969397063567628116694054128859081982023838277\ 035483496879734048888293016736770941584654400954862465146101353913496855912040\ 236361872150992980651905861682815302875042754525860533196343259577747881343723\ 939499124380614375449859068607518563142725525564259396701498041425981823785257\ 682943639596562438852065654807103884546394453770191784571874101186223227802525\ 194362657438242256093567692582387749116073775945140144703190224153559112506138\ 178297421264982641618724606313340891926702359795802365841631755679233566210123\ 133584549459059006998420067226025116774384736482438571540714626594564239112717\ 078030637141692638644010057131095896063264963755295676936468941051795200061645\ 202188435340473018243930514881984593076296404445687762416528716207276731860632\ 540801428874571198657307471701886603687970364770854852871670003622928528837468\ 246605881411754047446061676354303739923756596593696708792316774468569310838210\ 783048315919643002144125970228906320317410114936648095290301171633453191792293\ 924242877283787234956992923213609223494722645824375509451533552011761289751733\ 951371782933287158609438662701179184155458726489825139255594379519731786744876\ 992532617942338129994127939860264424519600605436818664670986594436593015437629\ 148697959769499653352721002002096791043948254724411334224487005463765684086676\ 215337362746159120547008629057169825735370523976123123841256434941178949861582\ 859702097109703919635216812258224756271951938272828520914718237534365525402074\ 620306673047695247009441381456178282666319613967359367257264603388494642489472\ 448978481596715306153846712236987128231978476931105716623637326207595971180401\ 514389623170601958570982381392466613527913695637655904861676205129740998314965\ 597860253410129454399867288300624408440186181511750687088764671609799292017769\ 624963301575829259618849485872002292248060628812177873383145882551293953651088\ 191865120044923154983947731473578688973142047310945381464822632102331079439597\ 462852354129575191063558792300195618131294612030157576340159785681751749842377\ 882447375398247457599686770740854557432942402678193848220354096210606072192499\ 082510485400318496319986322156908909761405310716511312932685349852440286448293\ 470591608586995981988903959955918110764134466588145254256588153545028884739975\ 324327809021522569521844145298650835512983980226238264974881811581525034599749\