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A107395
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a(n) = C(n+4,4)*C(n+6,4).
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1
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15, 175, 1050, 4410, 14700, 41580, 103950, 235950, 495495, 975975, 1821820, 3248700, 5569200, 9224880, 14825700, 23197860, 35441175, 52997175, 77729190, 112015750, 158858700, 222007500, 306101250, 416830050, 561117375, 747325215, 985483800, 1287547800
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OFFSET
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0,1
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LINKS
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FORMULA
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Sum_{n>=0} 1/a(n) = 16*Pi^2 - 3946/25.
Sum_{n>=0} (-1)^n/a(n) = 1776/25 - 512*log(2)/5. (End)
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EXAMPLE
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If n=0 then C(0+4,4)*C(0+6,4) = C(4,4)*C(6,4) = 1*15 = 15.
If n=9 then C(9+4,4)*C(9+6,4) = C(13,4)*C(15,4) = 715*1365 = 975975.
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MATHEMATICA
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Table[Binomial[n+4, 4]Binomial[n+6, 4], {n, 0, 30}] (* Harvey P. Dale, Jun 07 2019 *)
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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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