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A132228 a(n) = Sum_{k=0..n} C(n-1,k)^2*a(k)*a(n-k-1) for n>0 with a(0)=1. 0
1, 1, 2, 8, 52, 504, 6808, 122304, 2820048, 81183200, 2853990496, 120321094656, 5991955466560, 347996920977664, 23312947041336960, 1784445116557881344, 154767015393810489600, 15098457734490931766784 (list; graph; refs; listen; history; internal format)
OFFSET

0,3

PROG

(PARI) a(n)=if(n==0, 1, sum(k=0, n-1, a(k)*a(n-k-1)*binomial(n-1, k)^2 ))

CROSSREFS

Cf. A001059.

Sequence in context: A089467 A195192 A103239 * A151879 A191552 A154828

Adjacent sequences:  A132225 A132226 A132227 * A132229 A132230 A132231

KEYWORD

nonn

AUTHOR

Paul D. Hanna (pauldhanna(AT)juno.com), Aug 15 2007

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Last modified February 16 08:13 EST 2012. Contains 205893 sequences.