E.g.f. A(x) satisfies A(x) = exp( x^2 * A(x) / (1-x)^2 ) / (1-x).

A389867

E.g.f. A(x) satisfies A(x) = exp( x^2 * A(x) / (1-x)^2 ) / (1-x).

Terms

    a(0) =1a(1) =1a(2) =4a(3) =30a(4) =300a(5) =3780a(6) =58080a(7) =1056720a(8) =22251600a(9) =532843920a(10) =14309900640a(11) =426162068640

External references