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A137610
Self-convolution of A014062, where A014062(n) = C(n^2, n).
0
1, 2, 13, 180, 3844, 110908, 4030740, 176640072, 9059743648, 532179428700, 35219852623888, 2592514449263656, 210072673380786552, 18579938909696752728, 1780987027765227959096, 183907984490301947455872
OFFSET
0,2
FORMULA
a(n) = Sum_{k=0..n} C(k^2, k) * C((n-k)^2, n-k).
PROG
(PARI) a(n)=sum(k=0, n, binomial(k^2, k)*binomial((n-k)^2, n-k))
CROSSREFS
Cf. A014062.
Sequence in context: A183606 A366194 A307655 * A073178 A193192 A356491
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Jan 29 2008
STATUS
approved