a(n) = 21*(n+1)*binomial(n+6,9).

Terms

a(0) =84a(1) =1050a(2) =6930a(3) =32340a(4) =120120a(5) =378378a(6) =1051050a(7) =2642640a(8) =6126120a(9) =13273260a(10) =27159132a(11) =52907400a(12) =98760480a(13) =177578940a(14) =308897820a(15) =521694096a(16) =858049500a(17) =1377926550a(18) =2165313150a(19) =3336032700a(20) =5047562520a(21) =7511253750a(22) =11007400950a(23) =15903669600a(24) =22677454800a(25) =31942814904