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%I #11 May 10 2024 09:26:27
%S 1,6,56,1156,3656
%N Numbers k such that k and k^2 use only the digits 1, 3, 5 and 6.
%C Generated with DrScheme.
%H Jonathan Wellons, <a href="https://web.archive.org/web/20090206165028/http://jonathanwellons.com/shared-digits/">Tables of Shared Digits</a> [archived]
%e 3656^2 = 13366336.
%t With[{c={1,3,5,6}},Select[FromDigits/@Flatten[Table[Tuples[c,n],{n,4}],1],SubsetQ[ c,IntegerDigits[ #^2]]&]] (* _Harvey P. Dale_, May 26 2023 *)
%K base,nonn,more
%O 1,2
%A Jonathan Wellons (wellons(AT)gmail.com), Jan 22 2008