133856

Appears in sequences

• Let s(k) denote the sum of the even proper divisors of k. The sequence lists the pairs of numbers (x, y) such that s(x) = y and s(y) = x.at n=17A279812
• List of ordered pairs (x, y) from A279812.at n=18A279950
• Expansion of (1/2) * Sum_{k>0} (2 * x * (1 + x^k))^k.at n=17A360755