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A117251
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Column 0 of triangle A117250.
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1
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1, 1, -1, 4, -40, 896, -43008, 4325376, -899678208, 383862702080, -334114095890432, 590956713604022272, -2117988861556815822848, 15348576513041885002989568, -224527747847927003472304537600, 6621592717332784844802427579269120
(list;
graph;
refs;
listen;
history;
text;
internal format)
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OFFSET
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0,4
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LINKS
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FORMULA
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a(n) = (-1)^(n-1) * C(2*n,n)/(2*n-1) * 2^((n-1)*(n-2)/2-1).
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PROG
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(PARI) a(n)=(-1)^(n-1)*2^((n-1)*(n-2)/2-1)*binomial(2*n, n)/(2*n-1)
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CROSSREFS
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KEYWORD
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sign
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AUTHOR
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STATUS
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approved
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