This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A300950 #5 Mar 19 2018 22:09:56
%S A300950 3,4,7,8,11,12,15,48,51,52,55,56,59,60,63,64,67,68,71,72,75,76,79,112,
%T A300950 115,116,119,120,123,124,127,128,131,132,135,136,139,140,143,176,179,
%U A300950 180,183,184,187,188,191,192,195,196,199,200,203,204,207,240,243
%N A300950 Fixed points of A300948.
%C A300950 This sequence contains A007013(k) for any k > 0.
%C A300950 We can devise a set of primitive fixed points of A300948, say P, as follows:
%C A300950 - P contains the powers of 2, say 2^i, such that A300948(2^i) = 2^i (in that case, i = a(k)-1 for some k > 0),
%C A300950 - and the sums of two distinct powers of 2, say 2^i + 2^j, such that A300948(2^i) = 2^j,
%C A300950 - we can uniquely write any term of this sequence as a sum of distinct terms of P.
%F A300950 For any n > 0 with binary expansion Sum_{i=0..k} b_i * 2^i, a(n) = Sum_{i=0..k} b_i * p(i+1) (where p(i) denotes the i-th term of the set P described in the Comments section).
%e A300950 A300948(7) = 7 hence 7 belongs to this sequence.
%e A300950 A300948(42) = 25 hence 42 does not belong to this sequence.
%Y A300950 Cf. A007013, A300948.
%K A300950 nonn,base
%O A300950 1,1
%A A300950 _Rémy Sigrist_, Mar 16 2018