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 A160558 #6 Jul 22 2025 06:25:23 %S A160558 0,1,1,2,3,2,2,4,2,5,6,4,7,8,5,8,9,4,10,11,8,12,13,8,12,14,4,15,16,11, %T A160558 8,17,12,11,18,8,19,20,14,21,22,15,20,23,11,8,24,17,25 %N A160558 a(n) is the ordinal number of series in which the value of A160348(n) is defined. %C A160558 a(n)>=a((f(2n+1)-1)/2), where f is defined as in A159885. E.g., for n=4, we have a(4)=3>a(((9*3+1)/4-1)/2)=a(3)=2. %e A160558 Put a(0)=0. According to example to A160348, in the first series we find A160348(1) and A160348(2), therefore a(1)=a(2)=1. In the second series we find A160348(3), A160348(5), A160348(6) and A160348(8), thus a(3)=a(5)=a(6)=a(8)=2. %Y A160558 Cf A160348 A160322 A160266 A160267 A259667 A159945 A160198 A006519 A122458. %K A160558 nonn,uned %O A160558 0,4 %A A160558 _Vladimir Shevelev_, May 19 2009