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%I #11 Jul 05 2021 02:53:57
%S 0,1,4,10,40,100,400,1000,1071,4000,7776,10000,10710,10771,40000,
%T 77760,100000,106771,106776,107100,107710,400000,777600,1000000,
%U 1007046,1067710,1067760,1071000,1077100,1077776,4000000,6406771,7771774,7776000,10000000,10070460,10677100,10677600,10710000,10771000,10777760,40000000,64067710
%N Numbers k such that k and k^2 use only the digits 0, 1, 4, 6 and 7.
%C Generated with DrScheme.
%H Jonathan Wellons, <a href="/A136860/b136860.txt">Table of n, a(n) for n = 1..316</a>
%H Jonathan Wellons, <a href="https://web.archive.org/web/20090206165028/http://jonathanwellons.com/shared-digits/">Tables of Shared Digits</a>
%e 646076401416771^2 = 417414716467644616616040066441.
%t With[{c={0,1,4,6,7}},Select[FromDigits/@Tuples[c,8],SubsetQ[ c,IntegerDigits[ #^2]]&]] (* _Harvey P. Dale_, Jul 16 2020 *)
%Y Cf. A000290.
%K base,nonn
%O 1,3
%A Jonathan Wellons (wellons(AT)gmail.com), Jan 22 2008