A293141 E.g.f.: Product_{m>0} (1 - x^m + x^(2m)/2).

1, -1, -1, 0, 0, 0, 180, 0, 10080, 90720, 0, 0, 179625600, -1556755200, -10897286400, 326918592000, -2615348736000, -88921857024000, 800296713216000, -30411275102208000, 152056375511040000, 0, -351250227430502400000, -3231502092360622080000

Offset: 0

Author

Seiichi Manyama, Oct 01 2017

Keywords

• sign

Links

• Seiichi Manyama, Table of n, a(n) for n = 0..449

Crossrefs

Column k=2 of A293139.

Cf. A293138.

Programs

Maple

N:= 30: # to get a(0)..a(N)
P:= mul(1-x^m+x^(2*m)/2, m=1..N):
seq(coeff(P,x,n)*n!, n=0..N); # Robert Israel, Oct 01 2017