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A137018 Numbers k such that k and k^2 use only the digits 1, 2, 7, 8 and 9. 1

%I

%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="http://jonathanwellons.com/shared-digits/">Tables of Shared Digits</a>

%e 278787181898989^2 = 77722292791179979928199222121.

%K base,nonn

%O 1,2

%A Jonathan Wellons (wellons(AT)gmail.com), Jan 22 2008

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Last modified October 18 21:56 EDT 2021. Contains 348070 sequences. (Running on oeis4.)