a(n) = Sum_{k=1..floor(n/2)} sigma_k(n-k), where sigma_k(n) is the sum of the k-th powers of the divisors of n.
A343781
a(n) = Sum_{k=1..floor(n/2)} sigma_k(n-k), where sigma_k(n) is the sum of the k-th powers of the divisors of n.
Terms
- a(0) =0a(1) =1a(2) =3a(3) =9a(4) =17a(5) =55a(6) =111a(7) =457a(8) =943a(9) =4962a(10) =11148a(11) =69526a(12) =159402a(13) =1161340a(14) =2765874a(15) =22829766a(16) =55192956a(17) =510771772a(18) =1257880780a(19) =12870681814a(20) =32042113008a(21) =359566186586a(22) =904795505226
External references
- oeis: A343781