A136990 - OEIS

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

%S 1,2,5,11,12,15,21,22,112,122,211,221,285,1122,1488,1585,2211,2285,

%T 11141,12421,12428,15888,111585,124585,145415,241285,242511,285112,

%U 285515,285521,285522,1114112,1114815,1188522,1248285,1455512,1558285,1585185,2284488,2414218,2425185,2854515,11145511,11148285,11155485,12184112,12188282

%N Numbers k such that k and k^2 use only the digits 1, 2, 4, 5 and 8.

%C Generated with DrScheme.

%H Jonathan Wellons, <a href="/A136990/b136990.txt">Table of n, a(n) for n = 1..310</a>

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

%e 212418285828415^2 = 45121528154282212822821412225.

%t With[{c={1,2,4,5,8}},Select[Flatten[Table[FromDigits/@Tuples[c,n],{n,8}]],SubsetQ[c,IntegerDigits[#^2 ]]&]] (* _Harvey P. Dale_, Jun 12 2017 *)

%K base,nonn

%O 1,2

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