363639domain: NAppears in sequencesWhen squared gives number composed of digits {1,2,3}.at n=4A030175Numbers k such that k and k^2 use only the digits 1, 2, 3, 6 and 9.at n=47A136981Number of unlabeled connected loopless multigraphs with n edges rooted at two indistinguishable vertices.at n=9A339043