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 A078949 #16 Feb 21 2025 06:13:35
%S A078949 71,431,2339,2381,5849,6959,27791,32561,41609,45119,46439,48479,51419,
%T A078949 54401,63599,78779,81551,106859,115319,130631,138569,143501,153269,
%U A078949 166601,183569,196169,204359,229751,246929,266081,279119,321311,326999,350729,357659,362741
%N A078949 Primes p such that the differences between the 5 consecutive primes starting with p are (2,6,4,6).
%C A078949 Equivalently, primes p such that p, p+2, p+8, p+12 and p+18 are consecutive primes.
%H A078949 Amiram Eldar, <a href="/A078949/b078949.txt">Table of n, a(n) for n = 1..10000</a>
%F A078949 From _Amiram Eldar_, Feb 21 2025: (Start)
%F A078949 a(n) == 5 (mod 6).
%F A078949 a(n) == 11 or 29 (mod 30). (End)
%e A078949 71 is in the sequence since 71, 73 = 71 + 2, 79 = 71 + 8, 83 = 71 + 12 and 89 = 71 + 18 are consecutive primes.
%t A078949 Select[Partition[Prime[Range[50000]], 5, 1], Differences[#] == {2, 6, 4, 6} &][[;;, 1]] (* _Amiram Eldar_, Feb 21 2025 *)
%o A078949 (PARI) list(lim) = {my(p1 = 2, p2 = 3, p3 = 5, p4 = 7); forprime(p5 = 11, lim, if(p2 - p1 == 2 && p3 - p2 == 6 && p4 - p3 == 4 && p5 - p4 == 6, print1(p1, ", ")); p1 = p2; p2 = p3; p3 = p4; p4 = p5);} \\ _Amiram Eldar_, Feb 21 2025
%Y A078949 Subsequence of A078848. - _R. J. Mathar_, Feb 10 2013
%Y A078949 Cf. A001223, A078866, A078867, A078946-A078971, A022006, A022007.
%K A078949 nonn
%O A078949 1,1
%A A078949 _Labos Elemer_, Dec 19 2002
%E A078949 Edited by _Dean Hickerson_, Dec 20 2002