Search: id:A073003 Results 1-1 of 1 results found. %I A073003 %S A073003 5,9,6,3,4,7,3,6,2,3,2,3,1,9,4,0,7,4,3,4,1,0,7,8,4,9,9,3,6,9,2,7,9,3,7, %T A073003 6,0,7,4,1,7,7,8,6,0,1,5,2,5,4,8,7,8,1,5,7,3,4,8,4,9,1,0,4,8,2,3,2,7,2, %U A073003 1,9,1,1,4,8,7,4,4,1,7,4,7,0,4,3,0,4,9,7,0,9,3,6,1,2,7,6,0,3,4,4,2,3,7 %N A073003 Decimal expansion of -exp(1)*Ei(-1), also called Gompertz's constant. %C A073003 0! - 1! + 2! - 3! + 4! - 5! + ... = (Borel) sum_{n=0}^infinity (-y)^n n! = KummerU(1,1,1/y)/y %C A073003 Decimal expansion of phi(1) where phi(x)=integral(t=0,infinity, e^-t/ (x+t) dt ). - Benoit Cloitre (benoit7848c(AT)orange.fr), Apr 11 2003 %C A073003 Contribution from Johannes W. Meijer (meijgia(AT)hotmail.com), Oct 16 2009: (Start) %C A073003 The divergent series g(x=1,m) = 1^m*1! - 2^m*2! + 3^m*3! - 4^m*4! + ... , m=>-1, is intimately related to Gompertz's constant. We discovered that g(x=1,m) = (-1)^m * (A040027(m) - A000110(m+1) * A073003) with A000110 the Bell numbers and A040027 a sequence that was published by Gould, see for more information A163940. %C A073003 (End) %D A073003 Bruce C. Berndt, Ramanujan's notebooks Part II, Springer, p. 171 %D A073003 Bruce C. Berndt, Ramanujan's notebooks Part I, Springer, p. 144-145. %D A073003 Walls, H. S., Analytic Theory of Continued Fractions, Van Nostrand, New York, 1948, p. 356 %H A073003 Simon Plouffe, -exp(1)*Ei(-1) %H A073003 Eric Weisstein's World of Mathematics, Link to a section of The World of Mathematics %H A073003 Eric Weisstein's World of Mathematics, Exponential Integral %H A073003 A. I. Aptekarev, On linear forms containing the Euler constant, arXiv:0902.1768 [math.NT]. [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Feb 14 2009] %H A073003 G.H. Hardy, Divergent Series , Oxford University Press, 1949. p. 29. [From Johannes W. Meijer (meijgia(AT)hotmail.com), Oct 16 2009] %H A073003 Ed Sandifer, Divergent Series, How Euler Did It, MAA Online, June 2006. [From Johannes W. Meijer (meijgia(AT)hotmail.com), Oct 16 2009] %F A073003 phi(1)=e*(sum(k>=1, (-1)^(k-1)/k/k!) - Gamma)=0.596347362323194... where Gamma is the Euler constant. %F A073003 G = 0.596347... = 1/(1+1/(1+1/(1+2/(1+2/(1+3/(1+3/(1+4/(1+4/(1+5/(1+5/ (1+6/(...- Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Aug 14 2005 %e A073003 0.59634736232319407434... %t A073003 RealDigits[ N[ -Exp[1]*ExpIntegralEi[ -1], 110]] [[1]] %Y A073003 Contribution from Johannes W. Meijer (meijgia(AT)hotmail.com), Oct 16 2009: (Start) %Y A073003 Equals A001113*A099285. %Y A073003 (End) %Y A073003 Sequence in context: A134879 A051158 A117605 this_sequence A087498 A121060 A021630 %Y A073003 Adjacent sequences: A073000 A073001 A073002 this_sequence A073004 A073005 A073006 %K A073003 cons,nonn %O A073003 0,1 %A A073003 Robert G. Wilson v (rgwv(AT)rgwv.com), Aug 03 2002 %E A073003 Additional references from Gerald McGarvey (Gerald.McGarvey(AT)comcast.net), Oct 10 2005 %E A073003 Link corrected by Johannes W. Meijer (meijgia(AT)hotmail.com), Aug 01 2009 Search completed in 0.002 seconds