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A371826
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a(n) = Sum_{k=0..floor(n/2)} n^k * binomial(2*n-k,n-2*k).
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3
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1, 2, 8, 35, 170, 872, 4740, 26994, 161006, 1001009, 6476976, 43480373, 302250196, 2170406149, 16070240276, 122453910495, 958755921686, 7701233828576, 63381318474768, 533793776053926, 4595440308780620, 40400161269188412, 362367733795887848
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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) = [x^n] 1/((1-x-n*x^2) * (1-x)^n).
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PROG
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(PARI) a(n) = sum(k=0, n\2, n^k*binomial(2*n-k, n-2*k));
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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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