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 A250038 #25 Jan 21 2015 13:04:25
%S A250038 1,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,257,259,261,263,
%T A250038 265,267,269,271,273,274,275,276,277,278,279,280,281,282,283,284,285,
%U A250038 286,287,289,293,295,299,301,305,306,307,308,309,310,311,312,313,314
%N A250038 Numbers n such that m = floor(n/16) is coprime to n and, if nonzero, m is also a term of the sequence.
%C A250038 See the comments in A250040 which all apply, except for the setting of the base, b=16. In particular, they define the property RTC(b).
%C A250038 This particular list is an infinite subset of A248501.
%H A250038 Stanislav Sykora, <a href="/A250038/b250038.txt">Table of n, a(n) for n = 1..10000</a>
%H A250038 Stanislav Sykora, <a href="https://oeis.org/wiki/File:GeneticThreads.txt">PARI/GP scripts for genetic threads</a>, with code and comments.
%H A250038 Wikipedia, <a href="http://en.wikipedia.org/wiki/Coprime_integers">Coprime integers</a>
%o A250038 (PARI) See the link.
%o A250038 (PARI) is_rtc(n, b=16) = {while (((m=gcd(n\b, n)) == 1), if (m == 0, return (1)); if ((n=n\b) == 0, return (1));); return (0);} \\ _Michel Marcus_, Jan 18 2015
%Y A250038 Cf. A248501, A250039, A250040.
%Y A250038 Other lists of right-truncatable numbers with the property RTC(b): A250036 (b=4), A250040 (b=10), A250042 (b=9), A250044 (b=8), A250046 (b=7), A250048 (b=6), A250050 (b=5).
%K A250038 nonn,base
%O A250038 1,2
%A A250038 _Stanislav Sykora_, Dec 07 2014