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%I #12 Apr 12 2024 09:51:27
%S 1,2,11,12,21,111,132,271,421,1111,1171,1312,1332,2171,13332,34311,
%T 34312,133332,371111,417412,421111,473421,1214171,1333332,3337271,
%U 3427421,12137271,13333332,121337271,131423412,133333332,177232171,217433311,333432412,334232171,337227421,377774171,473743311,1114142412,1114142421,1114144171
%N Numbers k such that k and k^2 use only the digits 1, 2, 3, 4 and 7.
%C Generated with DrScheme.
%H Jonathan Wellons, <a href="/A136970/b136970.txt">Table of n, a(n) for n = 1..149</a>
%H J. Wellons, <a href="https://web.archive.org/web/20090206165028/http://jonathanwellons.com/shared-digits/">Tables of Shared Digits</a> [archived]
%e 217134132142421^2 = 47147231341242344447427741241.
%t Table[With[{c={1,2,3,4,7}},Select[FromDigits/@Tuples[c,n], SubsetQ[ c, IntegerDigits[ #^2]]&]],{n,10}]//Flatten (* _Harvey P. Dale_, Feb 24 2016 *) (* _Harvey P. Dale_, Feb 24 2016 *)
%K base,nonn,changed
%O 1,2
%A Jonathan Wellons (wellons(AT)gmail.com), Jan 22 2008
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