%I #54 Jun 27 2020 17:00:44
%S 0,1,2,3,4,5,8,10,12,15,16,17,32,34,48,51,64,68,80,85,128,136,160,170,
%T 192,204,240,255,256,257,512,514,768,771,1024,1028,1280,1285,2048,
%U 2056,2560,2570,3072,3084,3840,3855,4096,4112,4352,4369,8192,8224,8704
%N Fixed points of A331364.
%C These are the numbers with at most one kind of nonzero digit in any base of the form 2^2^k (with k >= 0).
%C If k belongs to the sequence, then A001196(k) also belongs to the sequence, and conversely.
%C For any positive term m:
%C - the number of runs of consecutive 1's in the binary representation of m is a power of 2,
%C - the runs of consecutive 1's in the binary representation of m have all the same length, a power of 2.
%C Apparently, for any k >= 0, there are A001316(k) nonzero terms with 1+k binary digits.
%H Rémy Sigrist, <a href="/A332520/b332520.txt">Table of n, a(n) for n = 1..6562</a>
%H Rémy Sigrist, <a href="/A332520/a332520.png">Binary plot of the terms < 2^2^10</a>
%H Rémy Sigrist, <a href="/A332520/a332520.gp.txt">PARI program for A332520</a>
%e The first terms, alongside their binary representation, are:
%e n a(n) bin(a(n))
%e -- ---- ---------
%e 1 0 0
%e 2 1 1
%e 3 2 10
%e 4 3 11
%e 5 4 100
%e 6 5 101
%e 7 8 1000
%e 8 10 1010
%e 9 12 1100
%e 10 15 1111
%e 11 16 10000
%e 12 17 10001
%e 13 32 100000
%e 14 34 100010
%e 15 48 110000
%e 16 51 110011
%o (PARI) See Links section.
%Y Cf. A001196, A001316, A331364.
%K nonn,base
%O 1,3
%A _Rémy Sigrist_, Jun 24 2020
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