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 A245568 #20 May 22 2025 10:21:39 %S A245568 5,17,617,857,1277,1427,1697,2087,2687,3557,4217,5417,5477,7307,8837, %T A245568 9437,10067,13877,17657,18287,20747,21587,23537,25577,27917,28547, %U A245568 30467,32117,32297,35507,37337,37547,40127,41177,41387,41957 %N A245568 Initial members of prime quadruples (n, n+2, n+24, n+26). %C A245568 This sequence is prime n, where there exist two twin prime pairs of (n, n+2, n+24, n+26). %C A245568 Excluding 5, this is a subsequence of each of the following: A128468 (a(n) = 30*n + 17), A039949 (Primes of the form 30n-13), A181605 (twin primes ending in 7). %C A245568 A253624 is a subsequence of this sequence. %H A245568 Karl V. Keller, Jr., <a href="/A245568/b245568.txt">Table of n, a(n) for n = 1..100000</a> %H A245568 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/PrimeQuadruplet.html">Prime Quadruplet.</a> %H A245568 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/TwinPrimes.html">Twin Primes</a> %H A245568 Wikipedia, <a href="http://www.wikipedia.org/wiki/Twin_prime">Twin prime</a> %e A245568 For n = 17, the numbers 17, 19, 41, 43 are primes. %t A245568 a245568[n_] := Select[Prime@ Range@ n, And[PrimeQ[# + 2], PrimeQ[# + 24], PrimeQ[# + 26]] &]; a245568[5000] (* _Michael De Vlieger_, Jan 11 2015 *) %o A245568 (Python) %o A245568 from sympy import isprime %o A245568 for n in range(1,10000001,2): %o A245568 if isprime(n) and isprime(n+2) and isprime(n+24) and isprime(n+26): print(n,end=', ') %Y A245568 Cf. A077800 (twin primes), A128468, A039949, A181605, A253624. %K A245568 nonn %O A245568 1,1 %A A245568 _Karl V. Keller, Jr._, Jan 09 2015