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A061659 Numbers k > 1 such that, in base 5, k and k^2 contain the same digits in the same proportion.

%I A061659 #9 Aug 24 2023 14:25:31
%S A061659 9726,10512,10904,12702,12886,13766,13898,14008,15086,37644,41156,
%T A061659 42006,42106,44048,44448,44578,44756,44826,48630,48664,49482,49626,
%U A061659 49652,49676,51704,52560,52582,54262,54520,54982,57922,59672,60778,63510,64430,64736,65432
%N A061659 Numbers k > 1 such that, in base 5, k and k^2 contain the same digits in the same proportion.
%H A061659 Alois P. Heinz, <a href="/A061659/b061659.txt">Table of n, a(n) for n = 1..1000</a>
%e A061659 9726 = 302401_5 and 9726^2 = 143204020301_5.
%p A061659 p:= n-> add(x^i, i=convert(n, base, 5)):
%p A061659 a:= proc(n) option remember; local k;
%p A061659       for k from 1+`if`(n=1, 0, a(n-1))
%p A061659       while p(k)*2<>p(k^2) do od; k
%p A061659     end:
%p A061659 seq(a(n), n=1..50);  # _Alois P. Heinz_, May 10 2015
%Y A061659 Cf. A061656, A061657, A061658, A061660, A061661, A061662, A061663, A114258, A061664.
%K A061659 base,easy,nonn
%O A061659 1,1
%A A061659 _Erich Friedman_, Jun 16 2001
%E A061659 Offset changed to 1 by _Alois P. Heinz_, May 10 2015