G.f.: exp( Sum_{n>=1} A322185(n)*x^n/n ), where A322185(n) = sigma(2*n) * binomial(2*n,n)/2.

A322186

G.f.: exp( Sum_{n>=1} A322185(n)*x^n/n ), where A322185(n) = sigma(2*n) * binomial(2*n,n)/2.

Terms

    a(0) =1a(1) =3a(2) =15a(3) =76a(4) =357a(5) =1662a(6) =8203a(7) =36609a(8) =169800a(9) =788024a(10) =3586350a(11) =15948147a(12) =73761986a(13) =324147729a(14) =1454796651a(15) =6544916640a(16) =28902107643a(17) =126842754933a(18) =567156315794

External references