OFFSET
1,4
LINKS
Michael I. Shamos, A catalog of the real numbers, (2011). See p. 36.
FORMULA
Equals (sin(1) + sinh(1))/2.
EXAMPLE
1/1! + 1/5! + 1/9! + ... = 1.008336089225848981767442...
MATHEMATICA
RealDigits[(Sin[1] + Sinh[1])/2, 10, 110] [[1]]
PROG
(PARI) suminf(k=0, 1/(4*k+1)!) \\ Michel Marcus, Apr 25 2020
CROSSREFS
KEYWORD
nonn,cons
AUTHOR
Ilya Gutkovskiy, Apr 24 2020
STATUS
approved