a(n) = Sum_{k=1..n} k * sigma_n(k).
A356128
a(n) = Sum_{k=1..n} k * sigma_n(k).
Terms
- a(0) =1a(1) =11a(2) =103a(3) =1373a(4) =20657a(5) =381795a(6) =7921825a(7) =187452793a(8) =4916743582a(9) =142471278944
External references
- oeis: A356128
A356128
a(n) = Sum_{k=1..n} k * sigma_n(k).