a(n) = binomial(n+8,n)*binomial(n+11,8).

Terms

a(0) =165a(1) =4455a(2) =57915a(3) =495495a(4) =3185325a(5) =16563690a(6) =73002930a(7) =281582730a(8) =972740340a(9) =3062330700a(10) =8904315420a(11) =24168856140a(12) =61764854580a(13) =149660993790a(14) =345855237750a(15) =766005304350