a(n) = n*(n + 1)*(n + 2)*(n + 3)/2.

Terms

a(0) =0a(1) =12a(2) =60a(3) =180a(4) =420a(5) =840a(6) =1512a(7) =2520a(8) =3960a(9) =5940a(10) =8580a(11) =12012a(12) =16380a(13) =21840a(14) =28560a(15) =36720a(16) =46512a(17) =58140a(18) =71820a(19) =87780a(20) =106260a(21) =127512a(22) =151800a(23) =179400a(24) =210600a(25) =245700a(26) =285012a(27) =328860a(28) =377580a(29) =431520