G.f.: B(x)*B(2!*x^2)*B(3!*x^3)*..., where B(x) is g.f. of A000142.
A126787
G.f.: B(x)*B(2!*x^2)*B(3!*x^3)*..., where B(x) is g.f. of A000142.
Terms
- a(0) =1a(1) =1a(2) =4a(3) =14a(4) =66a(5) =308a(6) =1888a(7) =12240a(8) =95640a(9) =827904a(10) =8106960a(11) =87387264a(12) =1035645312a(13) =13316300928a(14) =184988692800
External references
- oeis: A126787