3333515domain: NAppears in sequencesNumbers k such that k and k^2 use only the digits 1, 2, 3 and 5.at n=20A136973Numbers k such that k and k^2 use only the digits 1, 2, 3, 5 and 7.at n=40A136975Numbers k such that the decimal expansions of both k and k^2 have 1 as smallest digit and 5 as largest digit.at n=23A256889