G.f.: 1 = Sum_{n>=0} a(n)*x^n / Product_{k=1..n+1} (1+k*x)^3.

A193333

G.f.: 1 = Sum_{n>=0} a(n)*x^n / Product_{k=1..n+1} (1+k*x)^3.

Terms

    a(0) =1a(1) =3a(2) =21a(3) =244a(4) =4056a(5) =88770a(6) =2426553a(7) =79893084a(8) =3085719033a(9) =137035475333

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