E.g.f.: (2 + exp(3*x)) / (4 - exp(3*x)).

A228938

E.g.f.: (2 + exp(3*x)) / (4 - exp(3*x)).

Terms

    a(0) =1a(1) =2a(2) =10a(3) =66a(4) =570a(5) =6162a(6) =80010a(7) =1212066a(8) =20983770a(9) =408687282a(10) =8844164010a(11) =210530630466

External references