E.g.f.: exp( Sum_{n>=1} x^(n*(n+1)/2) / (n*(n+1)/2)! ).

A205799

E.g.f.: exp( Sum_{n>=1} x^(n*(n+1)/2) / (n*(n+1)/2)! ).

Terms

    a(0) =1a(1) =1a(2) =1a(3) =2a(4) =5a(5) =11a(6) =32a(7) =113a(8) =365a(9) =1373a(10) =6072a(11) =25279a(12) =115633a(13) =606321a(14) =3051413a(15) =16344785a(16) =98402881a(17) =576283953a(18) =3523586227a(19) =23840955908a(20) =158428389359

External references