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A125807 Central terms of odd-indexed rows of triangle A125806: a(n) = A125806(2n+1,n). 3
1, 3, 16, 119, 1070, 10762, 116546, 1330923, 15823388, 194168612, 2444224858, 31422225930, 411141476444, 5460849893348, 73474839110524, 999764999592077, 13738614091375204, 190450074950481408, 2660727794475865450 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,2
COMMENTS
Central terms of even-indexed rows of triangle A125806 equal A063075 (number of partitions of 2n^2 whose Ferrers-plot fits within a 2n X 2n box and cover an n X n box).
LINKS
PROG
(PARI) {a(n)=local(C_q=if(n==0, 1, prod(j=n+2, 2*n+1, 1-q^j)/prod(j=1, n, 1-q^j))); sum(i=0, (n+1)*n, polcoeff(C_q, i)^2)}
CROSSREFS
Cf. A125806 (triangle); A063075; A125808, A125809 (row sums).
Sequence in context: A190633 A220352 A333682 * A125222 A199670 A192783
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Dec 12 2006
STATUS
approved

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Last modified March 29 08:59 EDT 2024. Contains 371268 sequences. (Running on oeis4.)