----------------------------------------------------------------------------- The Catalan Constant. As calculated by Greg Fee using Maple Release 3 standard Catalan evaluation. This implementation uses 1 bit/term series of Ramanujan. Calculated on April 25 1996 in approx. 10 hours of CPU on a SGI R4000 machine. To do the same on your machine just type this. > catalan := evalf(Catalan,50100): bytes used=37569782748, alloc=5372968, time=38078.95 here are the 50000 digits (1000 lines of 50 digits each). it comes from formula 34.1 of page 293 of Ramanujan Notebooks,part I, the series used is by putting x--> -1/2 . in other words the formula used is : the ordinary formula for Catalan sum((-1)**(n+1)/(2*n+1)**2,n=0..infinity) and then you apply the Euler Transform to it : ref : Abramowitz & Stegun page , page 16. the article of Greg Fee that took those formulas appear in Computation of Catalan's constant using Ramanujan's Formula, by Greg Fee, ACM 1990, Proceedings of the ISAAC conference, 1990 (MAYBE 1989), held in Tokyo. catalan := 0. 91596559417721901505460351493238411077414937428167 21342664981196217630197762547694793565129261151062 48574422619196199579035898803325859059431594737481 15840699533202877331946051903872747816408786590902 47064841521630002287276409423882599577415088163974 70252482011560707644883807873370489900864775113225 99713434074854075532307685653357680958352602193823 23950800720680355761048235733942319149829836189977 06903640418086217941101917532743149978233976105512 24779530324875371878665828082360570225594194818097 53509711315712615804242723636439850017382875977976 53068370092980873887495610893659771940968726844441 66804621624339864838916280448281506273022742073884 31172218272190472255870531908685735423498539498309 91911596738846450861515249962423704374517773723517 75440708538464401321748392999947572446199754961975 87064007474870701490937678873045869979860644874974 64387206238513712392736304998503539223928787979063 36440323547845358519277777872709060830319943013323 16712476158709792455479119092126201854803963934243 49565375967394943547300143851807050512507488613285 64129344959502298722983162894816461622573989476231 81954200660718814275949755995898363730376753385338 13545031276817240118140721534688316835681686393272 93677586673925839540618033387830687064901433486017 29810699217995653095818715791155395603668903699049 39667538437758104931899553855162621962533168040162 73752130120940604538795076053827123197467900882369 17861557338912441722383393814812077599429849172439 76685756327180688082799829793788494327249346576074 90543874819526813074437046294635892810276531705076 54797449483994895947709278859119584872412786608408 85545978238124922605056100945844866989585768716111 71786662336847409949385541321093755281815525881591 50222824445444171860994658815176649607822367897051 92697113125713754543701243296730572468450158193130 16087766215650957554679666786617082347682558133518