Partial sums of A001157: Sum_{j=1..n} sigma_2(j).

Terms

a(0) =1a(1) =6a(2) =16a(3) =37a(4) =63a(5) =113a(6) =163a(7) =248a(8) =339a(9) =469a(10) =591a(11) =801a(12) =971a(13) =1221a(14) =1481a(15) =1822a(16) =2112a(17) =2567a(18) =2929a(19) =3475a(20) =3975a(21) =4585a(22) =5115a(23) =5965a(24) =6616a(25) =7466a(26) =8286a(27) =9336a(28) =10178a(29) =11478