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 A335366 #33 Jun 23 2025 21:59:03 %S A335366 2,3,7,23,89,113,139,199,523,887,1129,1327,1669,1831,2477,2971,4297, %T A335366 5591,9551,15683,16141,19333,19609,28229,30593,31397,31907,34061, %U A335366 35617,43331,44293,81463,82073,89689,134513,155921,162143,173359,188029,212701,265621 %N A335366 Primes preceding the first-occurrence gaps in A014320. %C A335366 Contains A002386 as a subsequence. First differs from A002386 at a(7)=139. This sequence is a permutation of all positive terms of A000230, in increasing order. See A002386 and A005250 for more references and links. %H A335366 Brian Kehrig, <a href="/A335366/b335366.txt">Table of n, a(n) for n = 1..777</a> (Terms 1..745 from Alexei Kourbatov). %H A335366 Alexei Kourbatov and Marek Wolf, <a href="https://arxiv.org/abs/2002.02115">On the first occurrences of gaps between primes in a residue class</a>, arXiv preprint arXiv:2002.02115 [math.NT], 2020. %H A335366 The Prime Gap List, <a href="https://primegap-list-project.github.io/lists/prime-gaps-first-occurrences/">First Occurrence Prime Gaps</a> %F A335366 a(n) = A335367(n) - A014320(n). %e A335366 The first two primes are 2 and 3, and the first prime gap is 3 - 2 = 1; so a(1)=2. The next prime is 5, and the next gap is 5 - 3 = 2; this gap size has not occurred before, so a(2)=3. The next prime is 7, and the next gap is 7 - 5 = 2; the gap size 2 has already occurred before, so nothing is added to the sequence. %o A335366 (PARI) my(isFirstOcc=vector(9999, j, 1), s=2); forprime(p=3, 1e8, my(g=p-s); if(isFirstOcc[g], print1(s, ", "); isFirstOcc[g]=0); s=p) %Y A335366 Cf. A000230, A002386, A014320, A330853, A330854, A334543, A334544, A335367. %K A335366 nonn %O A335366 1,1 %A A335366 _Alexei Kourbatov_, Jun 03 2020