Последовательность A000081 в OEIS = Number of rooted trees with n nodes (or connected functions with a fixed point)
Последовательность A257401 в OEIS // God's number for a Rubik's cube of size n X n X n (using the half turn metric).
Последовательность A018226 в OEIS. Первые магические числа: 2, 8, 20, 28, 50, 82, 126 // Magic numbers of nucleons: nuclei with one of these numbers of either protons or neutrons are more stable against nuclear decay.
