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%I #13 Apr 12 2024 09:51:27
%S 1,4,14,119,4119
%N Numbers k such that k and k^2 use only the digits 1, 4, 6 and 9.
%C Generated with DrScheme.
%H J. Wellons, <a href="https://web.archive.org/web/20090206165028/http://jonathanwellons.com/shared-digits/">Tables of Shared Digits</a> [archived]
%e 4119^2 = 16966161.
%o (PARI) isokd(d) = #setintersect([0,2,3,5,7,8], Set(d)) == 0;
%o isok(k) = isokd(digits(k)) && isokd(digits(k^2)); \\ _Michel Marcus_, Jun 24 2021
%K base,nonn,more,changed
%O 1,2
%A Jonathan Wellons (wellons(AT)gmail.com), Jan 22 2008
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