a(n) = n*(n+1)*(n+8)/6.

Terms

a(0) =0a(1) =3a(2) =10a(3) =22a(4) =40a(5) =65a(6) =98a(7) =140a(8) =192a(9) =255a(10) =330a(11) =418a(12) =520a(13) =637a(14) =770a(15) =920a(16) =1088a(17) =1275a(18) =1482a(19) =1710a(20) =1960a(21) =2233a(22) =2530a(23) =2852a(24) =3200a(25) =3575a(26) =3978a(27) =4410a(28) =4872a(29) =5365