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A127784
G.f. satisfies: A(x) = 1 + (x+x^2)*A(x+x^2)^2.
2
1, 1, 3, 11, 51, 266, 1540, 9681, 65291, 468401, 3551693, 28327029, 236731183, 2066583601, 18796448581, 177735656083, 1743920667437, 17725856560839, 186366309301259, 2024042644283702, 22679125592930412, 261873356070694571
OFFSET
0,3
LINKS
PROG
(PARI) {a(n)=local(A=1+x+x*O(x^n)); for(i=0, n, A=1+subst(x*A^2, x, x+x^2)); polcoeff(A, n)}
CROSSREFS
Sequence in context: A199212 A113283 A326519 * A112696 A346967 A192925
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Jan 28 2007
STATUS
approved