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%I #9 Apr 12 2024 09:51:26
%S 0,1,9,10,11,90,91,99,100,101,109,110,899,900,901,910,911,990,991,999,
%T 1000,1001,1009,1010,1011,1090,1091,1100,1101,1109,8989,8990,8999,
%U 9000,9001,9010,9011,9100,9101,9110,9900,9901,9909,9910,9990,9991,9999,10000,10001,10009,10010,10011,10090,10091,10099,10100,10109,10110,10900,10910,10991,11000
%N Numbers k such that k and k^2 use only the digits 0, 1, 2, 8 and 9.
%C Generated with DrScheme.
%H Jonathan Wellons, <a href="/A136835/b136835.txt">Table of n, a(n) for n = 1..1240</a>
%H J. Wellons, <a href="https://web.archive.org/web/20090206165028/http://jonathanwellons.com/shared-digits/">Tables of Shared Digits</a> [archived]
%e 298180989^2 = 88911902201018121.
%t odQ[n_]:=Module[{c=Union[IntegerDigits[n^2]]},And@@Table[MemberQ[{0,1,2,8,9},c[[i]]],{i,Length[c]}]]; Select[FromDigits/@Tuples[{ 0,1,2,8,9},5],odQ] (* _Harvey P. Dale_, Nov 24 2013 *)
%K base,nonn
%O 1,3
%A Jonathan Wellons (wellons(AT)gmail.com), Jan 22 2008