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A102231 Column 1 of triangle A102230 and equals the convolution of A032349 with A032349 shift right. 1
0, 1, 5, 32, 236, 1896, 16116, 142544, 1298524, 12100952, 114820964, 1105574400, 10775285836, 106098789832, 1053858546516, 10546951101360, 106249238782652, 1076554249491640, 10964085715303620, 112175072002688480 (list; graph; refs; listen; history; text; internal format)
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, k-2, 2^(i+1)*binomial(2*k-2, i)*binomial(k-1, i+1))/(k-1)))); return(polcoeff(Ser(B)^2+x*Ser(B)^4+x*O(x^n), n))}

CROSSREFS

Cf. A032349, A102230.

Sequence in context: A153396 A146965 A053157 * A127089 A208046 A198598

Adjacent sequences:  A102228 A102229 A102230 * A102232 A102233 A102234

KEYWORD

nonn

AUTHOR

Paul D. Hanna, Jan 01 2005

STATUS

approved

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Last modified April 16 10:34 EDT 2014. Contains 240577 sequences.