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 A230809 #20 Feb 16 2025 08:33:20 %S A230809 179,239,359,419,659,719,1019,1439,1499,1559,2039,2339,2399,2459,2699, %T A230809 2819,2939,3299,3359,3539,3779,4019,4919,5039,5279,5399,5639,6899, %U A230809 7079,9059,9419,9479,9539,10799,11519,11579,11699,11939,12119,12899,12959,13619 %N A230809 Primes p of the form 60*n + 59 such that 2*p + 1 is also prime. %C A230809 Primes p such that 2*p + 1 divides Lucas(p) and Mersenne(p). %H A230809 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/LucasNumber.html">Lucas Number</a> %H A230809 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/MersenneNumber.html">Mersenne Number</a> %F A230809 A005384 INTERSECT A142799. %F A230809 A002515 INTERSECT A215850. %e A230809 179 is in the sequence since it is prime and 359 is a factor of both Lucas(179) and Mersenne(179) = 2^179 - 1. %o A230809 (Magma) [p : p in [59..13619 by 60] | IsPrime(p) and IsPrime(2*p+1)]; %o A230809 (PARI) forstep(p=59, 13619, 60, if(isprime(p)&&isprime(2*p+1), print1(p, ", "))); %Y A230809 Subsequence of A142799, of A215850, and of A239548. Cf. A000032, A001348, A002515. %K A230809 nonn %O A230809 1,1 %A A230809 _Arkadiusz Wesolowski_, Oct 30 2013