10004999domain: NAppears in sequencesNumbers k such that k and k^2 have square decimal digits.at n=15A077439Numbers k such that k and k^2 use only the digits 0, 1, 3, 4 and 9.at n=38A136841Numbers k such that k and k^2 use only the digits 0, 1, 4, 5 and 9.at n=40A136858