A358966 a(n) = n!*Sum_{m=1..floor(n/2)} 1/(m*binomial(n-1,2*m-1)*n).

0, 0, 1, 1, 5, 9, 70, 178, 2132, 6900, 118536, 462936, 10606752, 48446496, 1397029824, 7305837120, 254261617920, 1498370192640, 61084867115520, 400578023738880, 18717879561984000, 135203360447232000, 7123176975979008000, 56195977439927808000

Offset

0,5

Links

Table of n, a(n) for n=0..23.

Formula

E.g.f.: (-Li_2(2*x-x^2)-2*Li_2(-x))/(2*x-2).

Prog

(Maxima)
a(n):=n!*sum(1/(m*(binomial(n-1, 2*m-1))*n), m, 1, floor(n/2));

Crossrefs

Sequence in context: A370613 A347991 A179100 * A304538 A306123 A365580

Adjacent sequences: A358963 A358964 A358965 * A358967 A358968 A358969

Keyword

nonn

Author

Vladimir Kruchinin, Dec 07 2022

Status

approved