G.f.: exp( Sum_{n>=1} x^n/n * Sum_{k=0..n} binomial(n,k)^3 * 2^k ).

A206177

G.f.: exp( Sum_{n>=1} x^n/n * Sum_{k=0..n} binomial(n,k)^3 * 2^k ).

Terms

    a(0) =1a(1) =3a(2) =15a(3) =93a(4) =657a(5) =5067a(6) =41579a(7) =357297a(8) =3181305a(9) =29133387a(10) =272939679a(11) =2605588317a(12) =25269158105a(13) =248367451299

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