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 A111931 #16 Oct 19 2017 10:38:28 %S A111931 11,67,24077,29041891,33699452071 %N A111931 Smallest prime p such that 1/2, 2/3, 3/4, ..., (m-1)/m are n-th power non-residues modulo p for maximum possible m (=A000236(n)). %C A111931 A000236(n) is the maximum length of a run of consecutive residues modulo prime p, starting with 1, where no two adjacent elements belong to the same n-th power residue class (in other words, there is no n-th power residue modulo p in the sequence of ratios 1/2, 2/3, ..., (A000236(n)-1)/A000236(n)). a(n) equals the smallest p admitting a run of maximum length A000236(n). %e A111931 a(2)=11 since A000236(2)=3 and 1/2=6, 2/3=8 are nonsquares modulo 11, and there is no smaller prime modulo which 1/2 and 2/3 are nonsquares. %Y A111931 Cf. A000236, A000445. %K A111931 hard,nonn,more %O A111931 2,1 %A A111931 _Max Alekseyev_, Aug 21 2005 %E A111931 a(6) from _Don Reble_, added by _Max Alekseyev_, Sep 03 2017