a(n) = sigma_{2n}(n^2)/sigma_n(n^2), where sigma_n(m) = Sum_{d|m} d^n.
A108223
a(n) = sigma_{2n}(n^2)/sigma_n(n^2), where sigma_n(m) = Sum_{d|m} d^n.
Terms
- a(0) =1a(1) =13a(2) =703a(3) =61681a(4) =9762501a(5) =2140365529a(6) =678222249307
External references
- oeis: A108223