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A089976
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Antidiagonal sums of array A089975.
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1
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1, 1, 2, 4, 8, 20, 52, 146, 458, 1498, 5240, 19562, 76006, 311258, 1334108, 5931250, 27492122, 132096626, 655783888, 3368747018, 17837850110, 97228103482, 545514383396, 3142793126018, 18578114240578, 112620106745570, 698987455899992, 4439420959115866, 28832596784976998, 191284437539842538
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OFFSET
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0,3
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LINKS
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PROG
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(PARI) T(n, k) = sum(i=max(0, n-k), floor(n/2), n!*k!/(2^i*(n-2*i)!*(k-n+i)!*i!)); \\ A089975
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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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