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%I #9 Apr 12 2024 09:51:27
%S 1,3,4,6,13,14,19,31,44,63,119,369,643,1146,1414,1914,3114,3364,4119,
%T 6414,6646,11914,11963,14119,31131,31614,34196,36694,44313,64313,
%U 64414,141313,191414,311343,316143,336696,363196,366946,411636,411694,641414,969119,1196646,1414194,1913469,3334114,3363646,3649196,3666969,3693196,4434114
%N Numbers k such that k and k^2 use only the digits 1, 3, 4, 6 and 9.
%C Generated with DrScheme.
%H Jonathan Wellons, <a href="/A137027/b137027.txt">Table of n, a(n) for n = 1..520</a>
%H J. Wellons, <a href="https://web.archive.org/web/20090206165028/http://jonathanwellons.com/shared-digits/">Tables of Shared Digits</a> [archived]
%e 641431341949136^2 = 411434166434669436443611146496.
%t sdQ[n_]:=Module[{idn2=Union[IntegerDigits[n^2]]},And@@Table[ MemberQ[ {1,3,4,6,9}, idn2[[i]]],{i,Length[idn2]}]]; Flatten[ Table[ Select[ FromDigits/@Tuples[{1,3,4,6,9},d],sdQ],{d,7}]] (* _Harvey P. Dale_, Jun 10 2013 *)
%K base,nonn,changed
%O 1,2
%A Jonathan Wellons (wellons(AT)gmail.com), Jan 22 2008
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