A193468 a(n) = A193466(n)/n for n>=1.

1, 1, 3, 21, 193, 2125, 32281, 655235, 15530705, 427214889, 14127457681, 542796582295, 23400843532969, 1140401734145453, 62743287535847465, 3822548966261363595, 256275705820386124321, 18923726002188870476497

Offset: 1

Author

Paul D. Hanna, Jul 27 2011

Keywords

• nonn

Comments

A193466 is defined by the e.g.f.: Sum_{n>=0} x^n * Product_{k=1..n} cosh(k*x).

Crossrefs

Cf. A193467.

Programs

PARI

{a(n)=local(X=x+x*O(x^n), Egf); Egf=sum(m=0, n, x^m*prod(k=1, m, cosh(k*X))); if(n<1,0,(n-1)!*polcoeff(Egf, n))}