a(n) = n*(n^2 - 1)*(n + 2)*(n^2 + 4*n + 6)/72.

Terms

a(0) =0a(1) =0a(2) =6a(3) =45a(4) =190a(5) =595a(6) =1540a(7) =3486a(8) =7140a(9) =13530a(10) =24090a(11) =40755a(12) =66066a(13) =103285a(14) =156520a(15) =230860a(16) =332520a(17) =468996a(18) =649230a(19) =883785a(20) =1185030a(21) =1567335a(22) =2047276a(23) =2643850a(24) =3378700a(25) =4276350a(26) =5364450a(27) =6674031a(28) =8239770a(29) =10100265