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A128563
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Column 2 of triangle A128562.
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1
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1, 4, 12, 29, 61, 120, 222, 392, 669, 1109, 1792, 2838, 4413, 6751, 10184, 15169, 22332, 32538, 46955, 67162, 95288, 134173, 187593, 260562, 359682, 493622, 673736, 914814, 1236057, 1662340, 2225738, 2967500, 3940540, 5212495, 6869598
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OFFSET
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0,2
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LINKS
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FORMULA
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a(n) is the coefficient of q^(2*n+6) in the q-binomial coefficient [2*n+5, n+2].
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PROG
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(PARI) a(n)=polcoeff(prod(j=n+3, 2*n+5, 1-q^j)/prod(j=1, n+3, 1-q^j), 2*n+6, q)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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