190899321domain: NAppears in sequencesa(n) = B(n) - 1, where B(n) = Bell numbers, A000110.at n=12A058692Number of set partitions of {1, ..., n} that avoid 7-nestings.at n=14A192128Number of arrays of n 0..12 integers with new values introduced in order 0..12 but otherwise unconstrained.at n=13A203643