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A137005 Numbers k such that k and k^2 use only the digits 1, 2, 5, 6 and 8. 2

%I

%S 1,5,11,15,16,25,81,125,261,285,511,515,516,816,1125,1285,1585,2261,

%T 2285,2581,2585,5125,11211,12511,12515,12581,25525,25615,26125,28615,

%U 28665,51211,81125,81585,112166,125125,158816,256615,258125,261125,261881,285515,515615,811516,828665,1118865,1585125,1681125,2261125,2285216,5162515,5185125

%N Numbers k such that k and k^2 use only the digits 1, 2, 5, 6 and 8.

%C Generated with DrScheme.

%H Jonathan Wellons, <a href="/A137005/b137005.txt">Table of n, a(n) for n = 1..435</a>

%H J. Wellons, <a href="http://jonathanwellons.com/shared-digits/">Tables of Shared Digits</a>

%e 828652861686516^2 = 686665565181252216515856218256.

%t With[{c={1,2,5,6,8}},Select[Flatten[Table[FromDigits/@Tuples[c,n],{n,7}]],SubsetQ[c,IntegerDigits[#^2]]&]] (* _Harvey P. Dale_, Apr 16 2015 *)

%K base,nonn

%O 1,2

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

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Last modified January 29 00:42 EST 2022. Contains 350670 sequences. (Running on oeis4.)