G.f.: Product_{k>=1} 1/(1-x^k)^(6*k).

Terms

a(0) =1a(1) =6a(2) =33a(3) =146a(4) =588a(5) =2160a(6) =7459a(7) =24354a(8) =76071a(9) =228420a(10) =663177a(11) =1868220a(12) =5124224a(13) =13718748a(14) =35932278a(15) =92242982a(16) =232473006a(17) =575971494a(18) =1404600837a(19) =3375138816a(20) =7998932769a(21) =18712911214a(22) =43246451181a(23) =98799885342a(24) =223269183076a(25) =499357990254