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A193468 a(n) = A193466(n)/n for n>=1. 1
1, 1, 3, 21, 193, 2125, 32281, 655235, 15530705, 427214889, 14127457681, 542796582295, 23400843532969, 1140401734145453, 62743287535847465, 3822548966261363595, 256275705820386124321, 18923726002188870476497 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

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

LINKS

Table of n, a(n) for n=1..18.

PROG

(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))}

CROSSREFS

Cf. A193467.

Sequence in context: A292361 A151388 A210670 * A132863 A202826 A212070

Adjacent sequences:  A193465 A193466 A193467 * A193469 A193470 A193471

KEYWORD

nonn

AUTHOR

Paul D. Hanna, Jul 27 2011

STATUS

approved

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Last modified May 10 21:07 EDT 2021. Contains 343780 sequences. (Running on oeis4.)