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 A241672 #19 Dec 20 2021 02:36:57 %S A241672 1,2,6,11,15,17,18,20,21,22,23,25,26,29,33,40,43,45,48,49,50,52,54,57, %T A241672 58,60,62,66,70,73,74,75,77,78,79,80,81,86,88,90,91,94,95,98,101,103, %U A241672 107,108,110,112,115,117,118,120,123,124,126,127,128,129,131,136,138,139,140,143,144,145,146 %N A241672 Numbers k such that A035014(k) begins with a 4. %C A241672 A023402(n) = 4 for numbers in the sequence, 3 for numbers not in the sequence. %e A241672 3 is not in the sequence because A035014(3) begins with a 3. %Y A241672 Cf. A035014, A023402, A241687 (complement). %K A241672 nonn,base %O A241672 1,2 %A A241672 _J. Lowell_, Apr 26 2014 %E A241672 More terms from _R. J. Mathar_, May 02 2014