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 A098421 #5 Feb 16 2025 08:32:54 %S A098421 5,23,37,47,67,71,73,97,113,191,199,223,233,277,281,283,307,317,347, %T A098421 349,353,457,467,613,617,619,641,643,647,821,829,853,863,877,887,1087, %U A098421 1097,1277,1279,1283,1297,1307,1423,1433,1447,1451,1453,1481,1493,1607,1609 %N A098421 Primes occurring in exactly one prime triple (p,q,r) with p<q<r=p+6. %C A098421 A098418(a(n)) = 1; subsequence of A098420. %H A098421 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/PrimeTriplet.html">Prime Triplet</a> %Y A098421 Cf. A098419, A098422, A098423. %K A098421 nonn %O A098421 1,1 %A A098421 _Reinhard Zumkeller_, Sep 07 2004