OFFSET
0,2
COMMENTS
The e.g.f. A(x) of this sequence also satisfies:
A(x*y) = Limit_{N->oo} [ Sum_{n>=0} (N + n*y)^(3*n) * (x/N^2)^n/n! ] / G(x,y)^N
where
G(x,y) = Limit_{N->oo} [ Sum_{n>=0} (N + n*y)^(3*n) * (x/N^2)^n/n! ]^(1/N)
for all real y.
EXAMPLE
E.g.f.: A(x) = 1 + 3*x + 54*x^2/2! + 1737*x^3/3! + 80460*x^4/4! + 4866075*x^5/5! + 363195144*x^6/6! + 32252007249*x^7/7! + 3320837109648*x^8/8! + 388974074329395*x^9/9! + 51071746190248800*x^10/10! +...
such that
A(x) = Limit_{N->oo} [ Sum_{n>=0} (N + n)^(3*n) * (x/N^2)^n/n! ] / F(x)^N
where
F(x) = Limit_{N->oo} [ Sum_{n>=0} (N + n)^(3*n) * (x/N^2)^n/n! ]^(1/N)
and
F(x) = 1 + x + 7*x^2/2! + 118*x^3/3! + 3373*x^4/4! + 139096*x^5/5! + 7565779*x^6/6! + 513277024*x^7/7! + 41820455065*x^8/8! + 3982842285184*x^9/9! + 434457816912991*x^10/10! +...+ A266482(n)*x^n/n! +...
CROSSREFS
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Dec 30 2015
STATUS
approved