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A061657 Numbers k > 1 such that, in base 3, k and k^2 contain the same digits in the same proportion.

%I A061657 #10 Aug 24 2023 14:22:27
%S A061657 184,196,464,500,544,550,552,584,588,622,626,670,706,1392,1436,1472,
%T A061657 1500,1552,1632,1650,1654,1656,1744,1752,1764,1866,1868,1878,1978,
%U A061657 2010,2030,2116,2118,3922,4136,4176,4308,4388,4416,4500,4656,4732,4756,4896,4900
%N A061657 Numbers k > 1 such that, in base 3, k and k^2 contain the same digits in the same proportion.
%H A061657 Alois P. Heinz, <a href="/A061657/b061657.txt">Table of n, a(n) for n = 1..10000</a>
%e A061657 184 = 20211_3 and 184^2 = 1201102221_3.
%p A061657 p:= n-> add(x^i, i=convert(n, base, 3)):
%p A061657 a:= proc(n) option remember; local k;
%p A061657       for k from 1+`if`(n=1, 0, a(n-1))
%p A061657       while p(k)*2<>p(k^2) do od; k
%p A061657     end:
%p A061657 seq(a(n), n=1..50);  # _Alois P. Heinz_, May 10 2015
%Y A061657 Cf. A061656, A061658, A061659, A061660, A061661, A061662, A061663, A114258, A061664.
%K A061657 base,easy,nonn
%O A061657 1,1
%A A061657 _Erich Friedman_, Jun 16 2001
%E A061657 Offset changed to 1 by _Alois P. Heinz_, May 10 2015