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A061658 Numbers k > 1 such that, in base 4, k and k^2 contain the same digits in the same proportion.

%I A061658 #7 Aug 24 2023 14:24:23
%S A061658 45,165,180,657,660,720,882,2165,2193,2331,2625,2628,2640,2880,3362,
%T A061658 3470,3528,3606,3683,3825,8285,8294,8337,8381,8477,8493,8519,8525,
%U A061658 8660,8721,8772,8817,9069,9282,9324,9479,9507,9869,9969,10185,10349,10353,10500,10512
%N A061658 Numbers k > 1 such that, in base 4, k and k^2 contain the same digits in the same proportion.
%H A061658 Alois P. Heinz, <a href="/A061658/b061658.txt">Table of n, a(n) for n = 1..1000</a>
%e A061658 45 = 231_4 and 45^2 = 133221_4.
%p A061658 p:= n-> add(x^i, i=convert(n, base, 4)):
%p A061658 a:= proc(n) option remember; local k;
%p A061658       for k from 1+`if`(n=1, 0, a(n-1))
%p A061658       while p(k)*2<>p(k^2) do od; k
%p A061658     end:
%p A061658 seq(a(n), n=1..50);  # _Alois P. Heinz_, May 10 2015
%Y A061658 Cf. A061656, A061657, A061659, A061660, A061661, A061662, A061663, A114258, A061664.
%K A061658 base,easy,nonn
%O A061658 1,1
%A A061658 _Erich Friedman_, Jun 16 2001
%E A061658 Offset changed to 1 by _Alois P. Heinz_, May 10 2015