A134184 A transform of the central binomial coefficients A001405.
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
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))};
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