login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A198946
G.f.: A(x) = exp( Sum_{n>=1} [Sum_{k=0..n} C(n,k)^n * A(x)^k] * x^n/n ).
1
1, 2, 7, 43, 661, 45503, 14835966, 19030289368, 96523753164218, 1826134533496656481, 136782939777235335759015, 38134547664565961218637677016, 42464787999263932204904982967955033, 176203582974534986934299369142808689004350
OFFSET
0,2
EXAMPLE
G.f.: A(x) = 1 + 2*x + 7*x^2 + 43*x^3 + 661*x^4 + 45503*x^5 +...
where
log(A(x)) = (1 + A(x))*x + (1 + 2^2*A(x) + A(x)^2)*x^2/2 +
(1 + 3^3*A(x) + 3^3*A(x)^2 + A(x)^3)*x^3/3 +
(1 + 4^4*A(x) + 6^4*A(x)^2 + 4^4*A(x)^3 + A(x)^4)*x^4/4 +
(1 + 5^5*A(x) + 10^5*A(x)^2 + 10^5*A(x)^3 + 5^5*A(x)^4 + A(x)^5)*x^5/5 +...
more explicitly,
log(A(x)) = 2*x + 10*x^2/2 + 95*x^3/3 + 2298*x^4/4 + 220502*x^5/5 + 88457005*x^6/6 +...
PROG
(PARI) {a(n)=local(A=1+x); for(i=1, n, A=exp(sum(m=1, n, sum(j=0, m, binomial(m, j)^m*(A+x*O(x^n))^j)*x^m/m))); polcoeff(A, n, x)}
CROSSREFS
Cf. A198945.
Sequence in context: A228230 A340335 A011835 * A212270 A270348 A270580
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Oct 31 2011
STATUS
approved