Triangular array, read by rows: T(n,k) = Sum_{d|n} d^k, 0 <= k < n.

Terms

a(0) =1a(1) =2a(2) =3a(3) =2a(4) =4a(5) =10a(6) =3a(7) =7a(8) =21a(9) =73a(10) =2a(11) =6a(12) =26a(13) =126a(14) =626a(15) =4a(16) =12a(17) =50a(18) =252a(19) =1394a(20) =8052a(21) =2a(22) =8a(23) =50a(24) =344a(25) =2402a(26) =16808a(27) =117650a(28) =4a(29) =15