a(n) = Sum{k=1 to n} sigma_{n-k+1}(k), where sigma_m(k) = sum{j|k} j^m.
A108672
a(n) = Sum{k=1 to n} sigma_{n-k+1}(k), where sigma_m(k) = sum{j|k} j^m.
Terms
- a(0) =1a(1) =4a(2) =10a(3) =27a(4) =73a(5) =227a(6) =767a(7) =2860a(8) =11569a(9) =50363a(10) =234155a(11) =1156037a(12) =6031747a(13) =33130183a(14) =190929773a(15) =1151198266a(16) =7243777228a(17) =47462906925a(18) =323188163747
External references
- oeis: A108672