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 A331205 #11 Jan 12 2020 13:35:47 %S A331205 2,3,5,549755813881,17,97,193,140737488355201,257,7681,15361, %T A331205 134215681,12289,8380417,114689 %N A331205 a(n) = least prime of the form 2^m - 2^n + 1. %C A331205 a(15) = 2^447 - 2^15 + 1 is too large to be represented in the data. %H A331205 Hugo Pfoertner, <a href="/A331205/b331205.txt">Table of n, a(n) for n = 0..62</a> %e A331205 See A331204. %o A331205 (PARI) for(n=0,14, for(m=n+1,oo, k=2^m-2^n+1; if(isprime(k), print1(k,", "); break))) %Y A331205 Cf. A181692, A331204 (corresponding values of m). %K A331205 nonn %O A331205 0,1 %A A331205 _Hugo Pfoertner_, Jan 12 2020