OFFSET
0,2
COMMENTS
LINKS
Paul D. Hanna, Table of n, a(n) for n = 0..200
FORMULA
E.g.f.: Sum_{n>=0} exp(n^2*x) * (1 - exp(-2*n*x))^n.
EXAMPLE
E.g.f.: A(x) = 1 + 2*x + 32*x^2/2! + 1298*x^3/3! + 98816*x^4/4! + 12116642*x^5/5! + 2181373952*x^6/6! + 541793612978*x^7/7! + ...
such that
A(x) = 1 + 2*sinh(x) + 4*sinh(2*x)^2 + 8*sinh(3*x)^3 + 16*sinh(4*x)^4 +...
or, equivalently,
A(x) = 1 + exp(x)*(1 - exp(-2*x)) + exp(4*x)*(1 - exp(-4*x))^2 + exp(9*x)*(1 - exp(-6*x))^3 + exp(16*x)*(1 - exp(-8*x))^4 + exp(25*x)*(1 - exp(-10*x))^5 + ...
RELATED SERIES.
A(log(1+x)) = 1 + 2*x + 15*x^2 + 201*x^3 + 3807*x^4 + 93103*x^5 + 2788528*x^6 + 98816388*x^7 + 4043274742*x^8 + ... + A319466(n)*x^n + ...
A(-log(1-x)) = 1 + 2*x + 17*x^2 + 233*x^3 + 4457*x^4 + 109599*x^5 + 3294200*x^6 + 117023348*x^7 + 4796944724*x^8 + ... + A319947(n)*x^n + ...
PROG
(PARI) {a(n) = n! * polcoeff(sum(k=0, n, 2^k * sinh(k*x + x*O(x^n))^k ), n)}
for(n=0, 30, print1(a(n), ", "))
CROSSREFS
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Oct 14 2018
STATUS
approved