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A229263

E.g.f.: Product_{n>=1} cosh(x^n).

1, 1, 13, 541, 32761, 3782521, 570649861, 126354119893, 34059666142321, 12697511966492401, 5418397453551516541, 2950382131846118771341, 1848796902719228099999593, 1394126061848631877574788201, 1187817128863650862040235107701, 1196980698779612997551160117313861

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,3

LINKS

Vaclav Kotesovec, Table of n, a(n) for n = 0..220

EXAMPLE

E.g.f.: A(x) = 1 + x^2/2! + 13*x^4/4! + 541*x^6/6! + 32761*x^8/8! +...

where

A(x) = cosh(x)*cosh(x^2)*cosh(x^3)*cosh(x^4)*cosh(x^5)*cosh(x^6)*...

PROG

(PARI) {a(n)=(2*n)!*polcoeff(prod(m=1, n, cosh(x^m +x*O(x^(2*n)))), 2*n)}

for(n=0, 20, print1(a(n), ", "))