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Search: a134185 -id:a134185
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A transform of the central binomial coefficients A001405.
+10
1
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
OFFSET
0,3
COMMENTS
Hankel transform is A134185.
FORMULA
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))};
KEYWORD
easy,nonn
AUTHOR
Paul Barry, Oct 11 2007
STATUS
approved

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