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A371357
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a(n) = 2^(n - HammingWeight(n)) * binomial(2*n, n).
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1
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1, 2, 12, 40, 560, 2016, 14784, 54912, 1647360, 6223360, 47297536, 180590592, 2769055744, 10650214400, 82158796800, 317680680960, 19696202219520, 76467608616960, 594748067020800, 2316387208396800, 36135640450990080, 141101072237199360, 1103153837490831360
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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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MAPLE
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HammingWeight := n -> add(convert(n, base, 2)):
a := n -> 2^(n - HammingWeight(n))*binomial(2*n, n):
seq(a(n), n = 0..22);
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MATHEMATICA
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Array[2^(# - DigitCount[#, 2, 1]) * Binomial[2*#, #] &, 25, 0] (* Paolo Xausa, Mar 31 2024 *)
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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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