A349204 a(n) = A065176(n + 2) * n! * [x^n](exp(x) / (1 + cos(x))).

1, 1, 3, 5, 5, 11, 111, 305, 235, 781, 5733, 22475, 48065, 217751, 8527167, 43899265, 30286495, 174772921, 2148821763, 13744073645, 46580213525, 327156548291, 9697877988981, 74211034240235, 149247386387155, 1236079055785861, 21456247956983193, 191231275195061015

Offset: 0

Author

Peter Luschny, Nov 14 2021

Keywords

• nonn

Crossrefs

Cf. A065176, A007814, A052928.

Programs

Maple

# Using function A065176(n).
egf := exp(x) / (1 + cos(x)): ser := series(egf, x, 30):
seq(A065176(n+2)*n!*coeff(ser, x, n), n = 0..27);

Formula

a(n) = 2^A007814(A052928(n+2))*n!*[x^n](exp(x) / (1 + cos(x))).