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 A139133 #19 Mar 05 2020 23:53:40 %S A139133 2,1,5,7,9,11,13,15,16,18,21,23,25,26,27,29,30,33,34,36,37,40,41,43, %T A139133 44,47,50,51,52,55,56,57,59,60,61,63,65,66,68,69,70,71,72,73,76,77,79, %U A139133 80,81,82,84,86,87,89,90,91,92,94,95,96,98,99 %N A139133 A self-descriptive sequence: positions of consonants in "two, one, five, seven, nine, eleven, thirteen, fifteen, ...". %C A139133 If there is a choice, pick the smallest number (or word) that makes sense. Hyphens and spaces are ignored. %D A139133 E. Angelini, "Jeux de suites", in Dossier Pour La Science, pp. 32-35, Volume 59 (Jeux math'), April/June 2008, Paris. %Y A139133 See A019270 (a version involving vowels rather than consonants) for further information. %Y A139133 For a French version of the "vowels" sequence see A139132. %K A139133 nonn,word,easy %O A139133 1,1 %A A139133 _N. J. A. Sloane_ %E A139133 Edited by _N. J. A. Sloane_, Jan 04 2016 at the suggestion of _Eric Angelini_ %E A139133 More terms from _Sean A. Irvine_, Jan 06 2016