163377domain: NAppears in sequencesNumber of binary rooted trees with n nodes and height at most 6.at n=37A036589Number of binary rooted trees with n nodes and height exactly 6.at n=37A036595Odd numbers k, not powers of primes, such that sigma(k) == 2 modulo 8 and sigma(sigma(k)) == 6 modulo 8.at n=27A332458