G.f.: Sum_{n>=0} x^n * Product_{k=1..n} (k - x) / (1 - k*x + x^2).

A231352

G.f.: Sum_{n>=0} x^n * Product_{k=1..n} (k - x) / (1 - k*x + x^2).

Terms

    a(0) =1a(1) =1a(2) =2a(3) =8a(4) =50a(5) =382a(6) =3434a(7) =35694a(8) =421682a(9) =5582158a(10) =81860978a(11) =1317457646a(12) =23087951666a(13) =437673142510

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