A218393 E.g.f. A(x) satisfies: Sum_{n>=0} 3^(n^2-n) * x^n/n! / A(3^n*x) = 1.

1, 1, 5, 429, 399273, 3072726201, 195746363156205, 107315772169710355749, 519518439242514267271247313, 22466597296811866577087885119239921, 8719095388372045822565716229498060925301845, 30421189091577923093547933001708849981738642279605789

Offset

0,3

Links

Table of n, a(n) for n=0..11.

Example

 E.g.f.: A(x) = 1 + x + 5*x^2/2! + 429*x^3/3! + 399273*x^4/4! + 3072726201*x^5/5! +...
where
1 = 1/A(x) + x/A(3*x) + 3^2*x^2/2!/A(3^2*x) + 3^6*x^3/3!/A(3^3*x) + 3^12*x^4/4!/A(3^4*x) + 3^20*x^5/5!/A(3^5*x) + 3^30*x^6/6!/A(3^6*x) +....

Prog

 (PARI) {a(n)=local(A=1+sum(k=1, n-1, a(k)*x^k/k!)+x*O(x^n)); n!*polcoeff(sum(k=0, n, 3^(k^2-k)*x^k/k!/subst(A, x, 3^k*x)), n)}
for(n=0, 15, print1(a(n), ", "))

Crossrefs

Cf. A054948.

Sequence in context: A217939 A147684 A199090 * A038003 A359992 A377724

Adjacent sequences: A218390 A218391 A218392 * A218394 A218395 A218396

Keyword

nonn

Author

Paul D. Hanna, Oct 27 2012

Status

approved