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 A051653 #16 Feb 24 2025 02:03:24 %S A051653 2,5,11,19,47,71,73,97,109,113,137,139,151,163,167,199,229,239,263, %T A051653 271,311,313,317,331,347,353,379,431,433,457,461,479,503,509,523,593, %U A051653 599,613,617,691,701,727,761,797,811,823,853,863,883,929,937,941,947,953 %N A051653 Primes p such that 2310*p + 1 is also prime. %H A051653 Amiram Eldar, <a href="/A051653/b051653.txt">Table of n, a(n) for n = 1..10000</a> %F A051653 a(n) = (A051649(n)-1)/2310. - _Amiram Eldar_, Feb 24 2025 %e A051653 p = 2 and 2310*p + 1 = 4621 are both primes. %t A051653 Select[Prime[Range[200]],PrimeQ[2310#+1]&] (* _Harvey P. Dale_, Oct 14 2014 *) %o A051653 (PARI) isok(k) = isprime(k) && isprime(2310*k+1); \\ _Amiram Eldar_, Feb 24 2025 %Y A051653 Cf. A005384, A002110, A005385, A051649. %K A051653 nonn %O A051653 1,1 %A A051653 _Labos Elemer_