Coefficient of x^n in Product_{k=1..n} (k + x + (n+1-k)*x^2), for n >= 0.

A322233

Coefficient of x^n in Product_{k=1..n} (k + x + (n+1-k)*x^2), for n >= 0.

Terms

    a(0) =1a(1) =1a(2) =6a(3) =27a(4) =350a(5) =2915a(6) =58156a(7) =714483a(8) =19279494a(9) =314352219a(10) =10702577028a(11) =217898279709

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