OFFSET
1,1
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 1..5000
FORMULA
Equals (1+erf(1))*e+1/sqrt(Pi), where erf is the error function (see A099286).
EXAMPLE
5.57316966431003975325790404977558240053838531356466534303248120641829030...
MATHEMATICA
RealDigits[(1 + Erf[1]) E + 1/Sqrt[Pi], 10, 90][[1]]
CROSSREFS
KEYWORD
nonn,cons
AUTHOR
Bruno Berselli, Mar 19 2013
STATUS
approved