A137137 - OEIS

%I #9 Apr 12 2024 09:51:27

%S 3,6,63,83,86,833,836,876,883,887,937,8363,8876,8887,8937,9687,9833,

%T 9883,79836,79867,93637,96633,96886,98333,98336,98376,98887,798367,

%U 798667,936876,936963,937383,968333,986833,988937,989833,989867,993367,998333,998367,7983667,7987363,7998336,7998667,8937387,8938667,9363637,9366637,9366786

%N Numbers k such that k and k^2 use only the digits 3, 6, 7, 8 and 9.

%C Generated with DrScheme.

%H Jonathan Wellons, <a href="/A137137/b137137.txt">Table of n, a(n) for n = 1..575</a>

%H J. Wellons, <a href="https://web.archive.org/web/20090206165028/http://jonathanwellons.com/shared-digits/">Tables of Shared Digits</a> [archived]

%e 968968363768376^2 = 938899689983963839367377677376.

%t With[{c={3,6,7,8,9}},Table[Select[FromDigits/@Tuples[c,n],SubsetQ[c,IntegerDigits[#^2]]&],{n,7}]]//Flatten (* _Harvey P. Dale_, Nov 18 2023 *)

%K base,nonn

%O 1,1

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