OFFSET
0,3
FORMULA
a(n) = n! * [x^n] 1 / (1 - Sum_{1 <= j <= n/2} x^j / j!).
a(n) ~ sqrt(Pi/2) * n^(n + 1/2) / (exp(n) * log(2)^(n+1)). - Vaclav Kotesovec, Dec 28 2023
MATHEMATICA
Table[n! SeriesCoefficient[1/(1 - Sum[x^j/j!, {j, 1, Floor[n/2]}]), {x, 0, n}], {n, 0, 21}]
CROSSREFS
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Dec 28 2023
STATUS
approved