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%I #9 Apr 12 2024 09:51:26
%S 0,2,5,20,45,50,52,200,205,450,455,500,502,505,520,745,755,2000,2005,
%T 2050,2245,4500,4550,4552,5000,5002,5005,5020,5045,5050,5052,5200,
%U 7450,7455,7550,20000,20005,20050,20500,20505,22450,22455,45000,45005,45500,45505,45520,50000,50002,50005,50020,50045,50050,50052,50200,50205,50450,50455,50500
%N Numbers k such that k and k^2 use only the digits 0, 2, 4, 5 and 7.
%C Generated with DrScheme.
%H Jonathan Wellons, <a href="/A136899/b136899.txt">Table of n, a(n) for n = 1..1343</a>
%H J. Wellons, <a href="https://web.archive.org/web/20090206165028/http://jonathanwellons.com/shared-digits/">Tables of Shared Digits</a> [archived]
%e 7074745752^2 = 50052027455442045504.
%t Module[{c={0,2,4,5,7},t},t=FromDigits/@Tuples[c,5];Select[t,SubsetQ[c, IntegerDigits[ #^2]]&]] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Dec 31 2016 *)
%K base,nonn
%O 1,2
%A Jonathan Wellons (wellons(AT)gmail.com), Jan 22 2008