E.g.f.: Sum_{n>=0} cosh(n*x) * tanh(x)^n.

A211209

E.g.f.: Sum_{n>=0} cosh(n*x) * tanh(x)^n.

Terms

    a(0) =1a(1) =1a(2) =2a(3) =7a(4) =56a(5) =541a(6) =5312a(7) =57667a(8) =742016a(9) =11113081a(10) =184604672a(11) =3330446527a(12) =65282226176

External references