681870domain: NAppears in sequencesNumber of ways of placing n labeled balls into n unlabeled (but 3-colored) boxes.at n=8A027710Cube of lower triangular matrix of A056857 (successive equalities in set partitions of n).at n=36A078938Triangle read by rows. T(n, k) = BellPolynomial(n, k).at n=39A350256