



0, 1, 5, 32, 236, 1896, 16116, 142544, 1298524, 12100952, 114820964, 1105574400, 10775285836, 106098789832, 1053858546516, 10546951101360, 106249238782652, 1076554249491640, 10964085715303620, 112175072002688480
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OFFSET

0,3


LINKS

Table of n, a(n) for n=0..19.


PROG

(PARI) {a(n)=local(B=vector(n+1, k, if(k==1, 1, sum(i=0, k2, 2^(i+1)*binomial(2*k2, i)*binomial(k1, i+1))/(k1)))); return(polcoeff(Ser(B)^2+x*Ser(B)^4+x*O(x^n), n))}


CROSSREFS

Cf. A032349, A102230.
Sequence in context: A146965 A243693 A053157 * A127089 A241769 A208046
Adjacent sequences: A102228 A102229 A102230 * A102232 A102233 A102234


KEYWORD

nonn


AUTHOR

Paul D. Hanna, Jan 01 2005


STATUS

approved



