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 A095967 #12 Nov 14 2019 19:57:02 %S A095967 1,2,6,9,20,46,58,64,69,110,158,178,186,268,424,624,641,1236,1593, %T A095967 2264,2870,5797,7518,7688,9300 %N A095967 Numbers n such that r3(k) * 2^n + 1 is prime, where r3() = A002277 and k is the number of decimal digits of 2^n. %C A095967 a(1) through a(25) have been proved to be prime with WinPFGW. a(25) has 5600 digits. No more terms up to 12800. %C A095967 Results were computed using the PrimeFormGW (PFGW) primality-testing program. - _Hugo Pfoertner_, Nov 14 2019 %e A095967 a(4)=9 because 333 * 2^9 + 1 = 170497, a prime. %K A095967 more,nonn,base %O A095967 1,2 %A A095967 _Jason Earls_, Jul 15 2004