OFFSET
0,3
FORMULA
Numerators of coefficients in expansion of cos(sqrt(x)) / (1 - x).
EXAMPLE
1, 1/2, 13/24, 389/720, 4357/8064, 1960649/3628800, 258805669/479001600, ...
MATHEMATICA
Table[Sum[(-1)^k/(2 k)!, {k, 0, n}], {n, 0, 15}] // Numerator
nmax = 15; CoefficientList[Series[Cos[Sqrt[x]]/(1 - x), {x, 0, nmax}], x] // Numerator
PROG
(PARI) a(n) = numerator(sum(k=0, n, (-1)^k/(2*k)!)); \\ Michel Marcus, May 24 2022
CROSSREFS
KEYWORD
nonn,frac
AUTHOR
Ilya Gutkovskiy, May 24 2022
STATUS
approved