127585domain: NAppears in sequencesa(n) = Sum_{d|n} sigma(n/d)*d^3.at n=43A027847Numbers k such that the sum of the numbers from 1 to k and that from 1 to k+1 share the same sum of divisors.at n=37A375819Numbers k such that s(k) = s(k+2), where s(k) is the sum of odd divisors of k (A000593).at n=21A387920