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 A268801 #16 Jan 18 2019 15:21:53 %S A268801 7,19,43,103,307,419,1367,2647,7411,7823,11239,11699,31511,47051, %T A268801 148063,288179,360779,425779,507347,666403,1414943,2199143,3358423, %U A268801 9287939,11512843,11648887,24315443,42454267,145555231,161720627,184008203,766669427 %N A268801 Primes 4k + 3 at the end of the maximal gaps in A268799. %C A268801 Subsequence of A002145. %C A268801 A268799 lists the corresponding record gap sizes. See more comments there. %H A268801 Alexei Kourbatov, <a href="/A268801/b268801.txt">Table of n, a(n) for n = 1..41</a> %H A268801 Alexei Kourbatov and Marek Wolf, <a href="https://arxiv.org/abs/1901.03785">Predicting maximal gaps in sets of primes</a>, arXiv preprint arXiv:1901.03785 [math.NT], 2019. %e A268801 The first two primes of the form 4k+3 are 3 and 7, so a(1)=7. The next prime of this form is 11; the gap 11-7 is not a record so no term is added to the sequence. The next prime of this form is 19; the gap 19-11=8 is a new record so a(2)=19. %o A268801 (PARI) re=0; s=3; forprime(p=7, 1e8, if(p%4!=3, next); g=p-s; if(g>re, re=g; print1(p", ")); s=p) %Y A268801 Cf. A002145, A084161, A268799, A268800. %K A268801 nonn %O A268801 1,1 %A A268801 _Alexei Kourbatov_, Feb 13 2016