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 A147782 #28 Jul 07 2024 13:06:20 %S A147782 2,7,31,859 %N A147782 Primes p such that 7^p - 2 is prime. %C A147782 m=7 in the PARI script. 13 is the next base prime for which this condition holds. In fact, the base prime q in q^p-2 is prime must be of the form 6n+1. %C A147782 This follows from the fact that if q = 6n-1, the binomial q^p = (6n-1)^p = 6h-1 for some h and q^p-2 = 6h-1-2 is divisible by 3 and thus not prime. %C A147782 a(5) > 90263. - _J.W.L. (Jan) Eerland_, Dec 11 2022 %C A147782 a(5) > 274120 using A090669. - _Michael S. Branicky_, Jul 07 2024 %F A147782 A000040 INTERSECT A090669. - _R. J. Mathar_, Jan 22 2009 %t A147782 Select[Prime[Range[150]],PrimeQ[7^#-2]&] (* _Harvey P. Dale_, Feb 20 2013 *) %o A147782 (PARI) g(n,m)=forprime(p=2,n,y=m^p-2;if(ispseudoprime(y),print1(p","))) %Y A147782 Cf. A000040, A090669. %K A147782 nonn,hard,more %O A147782 1,1 %A A147782 _Cino Hilliard_, Nov 12 2008 %E A147782 Offset corrected by _Mohammed Yaseen_, Jul 20 2023