login
A181535
G.f.: A(x) = exp( Sum_{n>=1} A(2^(n^2)*x^n)*x^n/n ).
1
1, 1, 3, 15, 145, 2489, 83021, 5402565, 697174827, 179186086779, 91923934089991, 94222398574777359, 193061880430280639843, 790974713509247761511635, 6480456214858268755580705051, 106182276664343738404944887223883
OFFSET
0,3
EXAMPLE
G.f.: A(x) = 1 + x + 3*x^2 + 15*x^3 + 145*x^4 + 2489*x^5 +...
The logarithm of the g.f. equals the series:
log(A(x)) = A(2*x)*x + A(2^4*x^2)*x^2/2 + A(2^9*x^3)*x^3/3 + A(2^16*x^4)*x^4/4 +...
PROG
(PARI) {a(n)=local(A=1+x); for(i=1, n, A=exp(sum(m=1, n, subst(A, x, 2^(m^2)*x^m+x*O(x^n))*x^m/m))); polcoeff(A, n)}
CROSSREFS
Cf. A181536.
Sequence in context: A288456 A230367 A293844 * A378017 A162078 A245069
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Oct 30 2010
STATUS
approved