A136839 - OEIS

%I #9 Apr 12 2024 09:51:26

%S 0,1,10,100,1000,1071,10000,10710,100000,107100,174071,370771,1000000,

%T 1071000,1170771,1740710,1743771,3707710,10000000,10710000,11707710,

%U 17334071,17407100,17437710,37077100,100000000,100370001,107100000,117077100,133310701,173340710,174071000,174073071,174377100,370771000,374713771,414017001

%N Numbers k such that k and k^2 use only the digits 0, 1, 3, 4 and 7.

%C Generated with DrScheme.

%H Jonathan Wellons, <a href="/A136839/b136839.txt">Table of n, a(n) for n = 1..230</a>

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

%e 414013773134071^2 = 171407404344710010137741033041.

%t With[{c={0,1,3,4,7}},Select[FromDigits/@Tuples[c,9],SubsetQ[ c, IntegerDigits[ #^2]]&]] (* _Harvey P. Dale_, May 06 2018 *)

%K base,nonn

%O 1,3

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