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%I #7 Apr 12 2024 09:51:27
%S 1,9,11,17,27,89,91,911,989,2777,2827,2877,9911,27877,28127,88189,
%T 88277,88877,98989,99891,172891,279127,282827,287891,988877,2879189,
%U 9989891,9998891,29711811,87919777,88978189,99899891,112818127,277817777,277871911,277987917,278781777,279781911,287919777,888812811,1727112877,2778718989
%N Numbers k such that k and k^2 use only the digits 1, 2, 7, 8 and 9.
%C Generated with DrScheme.
%H Jonathan Wellons, <a href="/A137018/b137018.txt">Table of n, a(n) for n = 1..158</a>
%H J. Wellons, <a href="https://web.archive.org/web/20090206165028/http://jonathanwellons.com/shared-digits/">Tables of Shared Digits</a> [archived]
%e 278787181898989^2 = 77722292791179979928199222121.
%K base,nonn
%O 1,2
%A Jonathan Wellons (wellons(AT)gmail.com), Jan 22 2008