OFFSET
1,1
EXAMPLE
8.83943924091904909456698024436203574171002846378309279604186339401138107...
2/1 + 2^3/(1*3) + 2^5/(1*3*5) + 2^7/(1*3*5*7) + 2^9/(1*3*5*7*9) + 2^11/(1*3*5*7*9*11) + 2^13/(1*3*5*7*9*11*13) + ...
MATHEMATICA
RealDigits[E^2 Sqrt[Pi/2] Erf[Sqrt[2]], 10, 100][[1]]
PROG
(PARI) suminf(k=0, 2^(2*k+1)/prod(i=0, k, (2*i+1))) \\ Michel Marcus, Apr 27 2018
CROSSREFS
KEYWORD
nonn,cons
AUTHOR
Bruno Berselli, Apr 27 2018
STATUS
approved