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A134184
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A transform of the central binomial coefficients A001405.
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1
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1, 1, 3, 7, 17, 43, 109, 279, 721, 1871, 4881, 12783, 33585, 88495, 233745, 618719, 1640833, 4358719, 11595841, 30890751, 82391297, 219995007, 588004737, 1573072383, 4211960065, 11286490879, 30265474305
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OFFSET
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0,3
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COMMENTS
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LINKS
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FORMULA
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G.f.: g(x(1+x)) where g(x) is the g.f. of A001405; a(n)=sum{k=0..n, binomial(k,n-k)*binomial(k,floor(k/2))}; a(n)=sum{k=0..floor(n/2), binomial(n-k,k)*binomial(n-k,floor((n-k)/2))};
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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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STATUS
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approved
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