A206151 G.f.: exp( Sum_{n>=1} A206152(n)*x^n/n ), where A206152(n) = Sum_{k=0..n} binomial(n,k)^(n+k).

1, 2, 7, 120, 16257, 22426576, 181974299842, 15238138790731690, 8413234043413844801094, 36597622942948070873495055416, 1557743574279376981523155294991683637, 377269728353963189455845962558983304322979834

Offset

0,2

Comments

Logarithmic derivative yields A206152.

Links

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

Example

G.f.: A(x) = 1 + 2*x + 7*x^2 + 120*x^3 + 16257*x^4 + 22426576*x^5 +...
where the logarithm of the g.f. begins:
log(A(x)) = 2*x + 10*x^2/2 + 326*x^3/3 + 64066*x^4/4 + 111968752*x^5/5 +...+ A206152(n)*x^n/n +...

Prog

(PARI) {a(n)=polcoeff(exp(sum(m=1, n+1, x^m/m*sum(k=0, m, binomial(m, k)^(m+k))+x*O(x^n))), n)}
for(n=0, 16, print1(a(n), ", "))

Crossrefs

Cf. A206152 (log), A184730.

Sequence in context: A034902 A101429 A270749 * A070521 A292433 A338181

Adjacent sequences: A206148 A206149 A206150 * A206152 A206153 A206154

Keyword

nonn

Author

Paul D. Hanna, Feb 04 2012

Status

approved