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 A213085 #22 Aug 14 2015 04:13:29 %S A213085 1,7,3,5,6,9,10,55,11,3521,246,21,52,89969,286,60827,22,57481,1501, %T A213085 31937,44,2977,49,27,40,39806401,110,16777,114,214293,24823,247,33, %U A213085 259274569,222,2739,70,5993,253217,1062899,72,2007,215,85,140,4187,50,75 %N A213085 First occurrence of n in A212844. %C A213085 It is conjectured that every integer n>=0 appears in A212844 at least once, and therefore every a(n) is defined. %C A213085 Indices of terms that are bigger than 2^32-1 and possibly undefined: 69, 91, 114, 127, 141, 157, 175, 181, 195, 301, 313, 339, ... %C A213085 Indices 69, 127, 175, 181, 301, 313, 339, ... correspond to terms that either do not exist or are greater than 2*10^12. - _Charles R Greathouse IV_, Aug 13 2015 %H A213085 Charles R Greathouse IV, <a href="/A213085/b213085.txt">Table of n, a(n) for n = 0..68</a> %e A213085 Smallest n such that A212844(n)=1 is 7, so a(1)=7. %o A213085 (PARI) a(n) = my(k=1); while(lift(Mod(2, k)^(k+2)) != n, k++); k; \\ _Michel Marcus_, Aug 14 2015 %Y A213085 Cf. A212844, A213381, A213407. %K A213085 nonn %O A213085 0,2 %A A213085 _Alex Ratushnyak_, Jul 22 2012