Sum of the numbers between the two n's in A026362.

Terms

a(0) =0a(1) =12a(2) =24a(3) =40a(4) =60a(5) =111a(6) =143a(7) =217a(8) =261a(9) =358a(10) =414a(11) =534a(12) =602a(13) =674a(14) =750a(15) =909a(16) =997a(17) =1179a(18) =1279a(19) =1383a(20) =1491a(21) =1712a(22) =1832a(23) =2076a(24) =2208a(25) =2344a(26) =2484a(27) =2767a(28) =2919a(29) =3225