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 A099439 #16 Nov 14 2019 17:16:22 %S A099439 4,10,14,16,26,50,56,70,116,2072,6250,13670,14216,14626,396128 %N A099439 Numbers k such that A000295(k) = 2^k-k-1 is prime. %C A099439 The next term is > 400000. %C A099439 Equals A063791 + 1. - Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 03 2008 %C A099439 Some of the results were computed using the PrimeFormGW (PFGW) primality-testing program. - _Hugo Pfoertner_, Nov 14 2019 %e A099439 a(1) = 4 because 2^4 - 4 - 1 = 11 is prime. %Y A099439 Cf. A000295 (2^n-n-1), A099440 (primes in A000295), A099441 (2^n-n-1 is a semiprime), A099442 (semiprimes in A000295). %K A099439 nonn,more,hard %O A099439 1,1 %A A099439 _Hugo Pfoertner_, Oct 18 2004 %E A099439 a(15) (a PRP) from _Karsten Bonath_, Jun 07 2018