a(n) = (n^4 + n)/2 (Row sums of an n X n X n magic cube, when it exists).

Terms

a(0) =0a(1) =1a(2) =9a(3) =42a(4) =130a(5) =315a(6) =651a(7) =1204a(8) =2052a(9) =3285a(10) =5005a(11) =7326a(12) =10374a(13) =14287a(14) =19215a(15) =25320a(16) =32776a(17) =41769a(18) =52497a(19) =65170a(20) =80010a(21) =97251a(22) =117139a(23) =139932a(24) =165900a(25) =195325a(26) =228501a(27) =265734a(28) =307342a(29) =353655