146139

Appears in sequences

• Number of n-node unlabeled rooted trees with thinning limbs and root outdegree (branching factor) 2.at n=20A244703
• Numbers k such that s(k) = s(k-1) + s(k-2), where s(k) is the sum of proper divisors of k (A001065).at n=3A291176
• Solutions k of the equation s(k) = s(k-1) + s(k-2) where s(k) = usigma(k) - k is the sum of proper unitary divisors of k (A063919).at n=5A332974
• Solutions k of the equation s(k) = s(k-1) + s(k-2) where s(k) = isigma(k) - k is the sum of proper infinitary divisors of k (A126168).at n=6A332976