1948617

Appears in sequences

• a(n) = n*3^n.at n=11A036290
• a(n) = (2n-1) * 3^(2n-1).at n=5A060851
• a(n) = 11*3^n.at n=11A120354
• Numbers n that form a Pythagorean quadruple with n', n'' and sqrt(n^2 + n'^2 + n''^2), where n' and n'' are the first and the second arithmetic derivative of n.at n=12A230543
• Numbers with prime factorization of the form p_1^p_2*p_2^p_3*...p_(n-1)^p_n*p_n where p_(n-1) < p(n) and n > 1.at n=10A294110
• Let S = smallest missing positive number, adjoin S, 3*S, 9*S, 27*S, 81*S, ... to the sequence until reaching a term that has S as a substring; reset S to the smallest missing positive number, repeat.at n=43A331631
• The number of nonequivalent root ancestral configurations in a recursively defined family of gene trees and species trees with at least n = 9 leaves, in which for n >= 12 leaves, 3-leaf trees are successively added at the root of the tree with n-3 leaves.at n=31A355118