G.f. Product_{n>=1} (1 + a(n)*x^n) = Sum_{n>=0} n!*x^n.

A158094

G.f. Product_{n>=1} (1 + a(n)*x^n) = Sum_{n>=0} n!*x^n.

Terms

    a(0) =1a(1) =2a(2) =4a(3) =20a(4) =92a(5) =580a(6) =4156a(7) =34372a(8) =314348a(9) =3204116a(10) =35703996a(11) =433587396a(12) =5687955724a(13) =80265513140

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