a(n) = binomial(n+4,4)*binomial(n+7,7).

Terms

a(0) =1a(1) =40a(2) =540a(3) =4200a(4) =23100a(5) =99792a(6) =360360a(7) =1132560a(8) =3185325a(9) =8179600a(10) =19467448a(11) =43439760a(12) =91706160a(13) =184497600a(14) =355816800a(15) =661028544a(16) =1187785665a(17) =2071432440a(18) =3516320500a(19) =5824819000a(20) =9436206780a(21) =14978106000a(22) =23333661000a(23) =35728290000a(24) =53840548125a(25) =79942445856