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A113857
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a(n) = binomial(4+2*n, n) * binomial(9+2*n, 4+n).
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1
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126, 2772, 48048, 772200, 12033450, 184940756, 2824549728, 43028530272, 655081791000, 9977399586000, 152112583402560, 2322021633001200, 35496198345658050, 543418421128852500, 8331507823355640000, 127919340117331963200, 1966759854303978934200, 30279186980267369086800
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OFFSET
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0,1
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COMMENTS
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If one uses the "table" view of array A062190, the sequence appears as the fourth column right from the middle in the "formatted as a triangular array" subpanel.
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LINKS
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FORMULA
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EXAMPLE
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a(0) = C(4+2*n,n)*C(9+2*n,4+n) = C(4,0)*C(9,4) = 1*126 = 126.
a(7) = C(4+2*7,7)*C(9+2*7,4+7) = C(18,7)*C(23,11) = 31824*1352078 = 43028530272.
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PROG
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(PARI) a(n)={binomial(4+2*n, n) * binomial(9+2*n, 4+n)} \\ Andrew Howroyd, Jan 07 2020
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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