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 A037036 #8 Sep 28 2013 01:35:05 %S A037036 0,0,0,2,0,2,4,2,0,4,4,10,4,2,4,20,0,2,6,2,4,10,4,16,4,40,6,40,58,4, %T A037036 36,2,6,10,42,32,6,26,46,8,88,22,12,58,18,56,22,116,60,82,28,130,48, %U A037036 112,34,56,6,14,28,56,94,2,58,26,60,50,6,20,24,20,36,232,94,70,36,98,16,34 %N A037036 Least k such that 2^n+1-k is a prime. %e A037036 a(5)=2 because 2^5+1-2=31 that is a prime. %o A037036 (PARI) a(n) = my(k = 0); while (! isprime(2^n+1-k), k++); k; \\ _Michel Marcus_, Sep 28 2013 %Y A037036 Cf. A016014. %K A037036 nonn %O A037036 0,4 %A A037036 _Felice Russo_ %E A037036 More terms from _Erich Friedman_