a(n) = binomial(n+7,7) * binomial(n+10,10).

Terms

a(0) =1a(1) =88a(2) =2376a(3) =34320a(4) =330330a(5) =2378376a(6) =13741728a(7) =66745536a(8) =281582730a(9) =1056804320a(10) =3593134688a(11) =11224833984a(12) =32583198648a(13) =88687996320a(14) =228054847680a(15) =557467405440