a(n) = T(2n-1,n), array T given by A048201.

Terms

a(0) =1a(1) =6a(2) =17a(3) =37a(4) =63a(5) =98a(6) =139a(7) =186a(8) =240a(9) =298a(10) =359a(11) =431a(12) =505a(13) =589a(14) =683a(15) =779a(16) =892a(17) =1018a(18) =1150a(19) =1288a(20) =1431a(21) =1593a(22) =1762a(23) =1949a(24) =2151a(25) =2366a(26) =2591a(27) =2823a(28) =3061a(29) =3304