%I #7 Apr 12 2024 09:51:27
%S 1,2,7,11,12,21,27,171,212,421,479,2729,2777,4911,4912,11171,21729,
%T 44127,49777,112912,119127,221911,279271,471479,477412,492921,497212,
%U 499479,974229,1194771,1214171,2174229,2219171,4412729,4471479,4721729,4794911,4919271,4927421,4929277,4994777,4997212,4997271,4997277,4997777,9997212,12129271
%N Numbers k such that k and k^2 use only the digits 1, 2, 4, 7 and 9.
%C Generated with DrScheme.
%H Jonathan Wellons, <a href="/A136998/b136998.txt">Table of n, a(n) for n = 1..540</a>
%H J. Wellons, <a href="https://web.archive.org/web/20090206165028/http://jonathanwellons.com/shared-digits/">Tables of Shared Digits</a> [archived]
%e 492421742492421^2 = 242479172479272177477242441241.
%K base,nonn
%O 1,2
%A Jonathan Wellons (wellons(AT)gmail.com), Jan 22 2008