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.

A361480 a(n) is the greatest integer whose binary expansion has the same multiset of run-lengths as that of n.

This page as a plain text file.
%I A361480 #18 Mar 30 2023 15:28:38
%S A361480 0,1,2,3,6,5,6,7,14,13,10,13,12,13,14,15,30,29,26,27,26,21,26,29,28,
%T A361480 27,26,27,28,29,30,31,62,61,58,59,54,53,54,59,58,53,42,53,54,53,58,61,
%U A361480 60,59,54,51,54,53,54,59,56,59,58,59,60,61,62,63,126,125
%N A361480 a(n) is the greatest integer whose binary expansion has the same multiset of run-lengths as that of n.
%H A361480 Rémy Sigrist, <a href="/A361480/b361480.txt">Table of n, a(n) for n = 0..8191</a>
%H A361480 <a href="/index/Bi#binary">Index entries for sequences related to binary expansion of n</a>
%F A361480 a(a(n)) = a(n).
%F A361480 a(n) >= n.
%o A361480 (PARI) a(n) = { my (r=[]); while (n, my (v=valuation(n+n%2, 2)); n\=2^v; r=concat(v, r)); r=vecsort(r); my (h=0, t=#r+1, v=0); for (k=1, #r, v=(v+k%2)*2^if (k%2, r[t--], r[h++])-k%2;); return (v); }
%Y A361480 Cf. A073138, A335835, A361478, A361479.
%K A361480 nonn,look,base
%O A361480 0,3
%A A361480 _Rémy Sigrist_, Mar 13 2023