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 A013948 #11 Jul 27 2022 16:35:30 %S A013948 2,3,6,8,9,11,12,15,18,19,21,24,26,27,30,33,35,36,38,39,42,44,45,47, %T A013948 50,53,54,56,57,60,62,63,65,66,69,72,74,75,77,80,81,83,84,87,89,90,92, %U A013948 93,96,99,100,102,105,107,108,110,111,114,117,119,120,123,126,127,129,132,135 %N A013948 Positions of 2's in Kolakoski sequence (A000002). %F A013948 Numbers n such that A078649(A054353(n-1)-n+2)-A054353(n-1)=1. [_Benoit Cloitre_, Feb 08 2009] %F A013948 Least k such that A054353(k)>=A078649(n). a(n)=A078649(n)-n+1. [_Benoit Cloitre_, Feb 07 2009] %Y A013948 Cf. A000002, A054353, A078649. %Y A013948 Complement: A013947. %K A013948 nonn,easy %O A013948 1,1 %A A013948 _Clark Kimberling_