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%I #9 Apr 12 2024 09:51:26
%S 0,2,5,20,45,50,200,205,450,500,502,505,2000,2005,2050,2245,4500,5000,
%T 5002,5005,5020,5045,5050,20000,20005,20050,20500,20505,22450,45000,
%U 45005,50000,50002,50005,50020,50045,50050,50200,50205,50450,50500,50502,200000,200005,200050,200500,200505,205000,205050,224500,450000,450005,450045,450050
%N Numbers k such that k and k^2 use only the digits 0, 2, 4 and 5.
%C Generated with DrScheme.
%H Jonathan Wellons, <a href="/A136897/b136897.txt">Table of n, a(n) for n = 1..1179</a>
%H J. Wellons, <a href="https://web.archive.org/web/20090206165028/http://jonathanwellons.com/shared-digits/">Tables of Shared Digits</a> [archived]
%e 505524500450^2 = 255555020555222050202500.
%t Module[{c={0,2,4,5}},Select[FromDigits/@Tuples[c,6], SubsetQ[c, IntegerDigits[ #^2]]&]] (* _Harvey P. Dale_, Jul 30 2015 *)
%K base,nonn
%O 1,2
%A Jonathan Wellons (wellons(AT)gmail.com), Jan 22 2008