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%I #10 Dec 28 2024 11:39:40
%S 0,3,6,30,60,63,64,300,306,600,603,630,636,640,3000,3006,3060,6000,
%T 6003,6030,6300,6360,6400,6636,30000,30006,30060,30600,60000,60003,
%U 60030,60300,63000,63600,64000,66360,300000,300006,300060,300600,306000,600000,600003,600030,600300,603000,630000,636000,640000,663600,949003,3000000,3000006
%N Numbers k such that k and k^2 use only the digits 0, 3, 4, 6 and 9.
%C Generated with DrScheme.
%H Jonathan Wellons, <a href="/A136932/b136932.txt">Table of n, a(n) for n = 1..888</a>
%H J. Wellons, <a href="https://web.archive.org/web/20090206165028/http://jonathanwellons.com/shared-digits/">Tables of Shared Digits</a> [archived]
%e 969360639630393^2 = 939660049664644643999649334449.
%t Module[{nn=7,c={0,3,4,6,9}},Select[FromDigits/@Tuples[c,nn],SubsetQ[c,IntegerDigits[#^2]]&]] (* _Harvey P. Dale_, Dec 28 2024 *)
%K base,nonn
%O 1,2
%A Jonathan Wellons (wellons(AT)gmail.com), Jan 22 2008