a(n) = n! * Sum_{k=1..n} sigma_k(k)/k.
A356437
a(n) = n! * Sum_{k=1..n} sigma_k(k)/k.
Terms
- a(0) =1a(1) =7a(2) =77a(3) =1946a(4) =84754a(5) =6202524a(6) =636369348a(7) =89979720144
External references
- oeis: A356437
A356437
a(n) = n! * Sum_{k=1..n} sigma_k(k)/k.