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

Terms

a(0) =120a(1) =2640a(2) =28512a(3) =205920a(4) =1132560a(5) =5096520a(6) =19631040a(7) =66745536a(8) =204787440a(9) =576438720a(10) =1507608960a(11) =3700494720a(12) =8593371072a(13) =19004570640a(14) =40244973120a(15) =81980500800a(16) =161264274600a(17) =307350735120a(18) =569168028000