a(n) = (n+1)*binomial(n+5, 5).

Terms

a(0) =1a(1) =12a(2) =63a(3) =224a(4) =630a(5) =1512a(6) =3234a(7) =6336a(8) =11583a(9) =20020a(10) =33033a(11) =52416a(12) =80444a(13) =119952a(14) =174420a(15) =248064a(16) =345933a(17) =474012a(18) =639331a(19) =850080a(20) =1115730a(21) =1447160a(22) =1856790a(23) =2358720a(24) =2968875a(25) =3705156a(26) =4587597a(27) =5638528a(28) =6882744a(29) =8347680