cp's OEIS Frontend

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.

A342699 Numbers k such that A342698(k) = k.

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%I A342699 #8 Mar 20 2021 14:38:23
%S A342699 0,1,3,7,9,12,15,17,19,24,25,28,31,33,35,39,48,49,51,56,57,60,63,65,
%T A342699 67,71,79,96,97,99,103,112,113,115,120,121,124,127,129,131,135,143,
%U A342699 153,159,192,193,195,199,204,207,224,225,227,231,240,241,243,248,249
%N A342699 Numbers k such that A342698(k) = k.
%C A342699 Equivalently, these are the numbers k such that each bit in the binary representation of k is next to a bit with the same value (and we consider that the first bit is next to the last bit). Hence, all terms of A033015 belong to this sequence.
%H A342699 Rémy Sigrist, <a href="/A342699/b342699.txt">Table of n, a(n) for n = 1..10000</a>
%o A342699 (PARI) is(n) = my (w=#binary(n)); sum(k=0, w-1, ((bittest(n, (k-1)%w)+bittest(n, k%w)+bittest(n, (k+1)%w))>=2) * 2^k)==n
%Y A342699 Cf. A033015, A342698.
%K A342699 nonn,base
%O A342699 1,3
%A A342699 _Rémy Sigrist_, Mar 18 2021