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 A086865 #13 Sep 27 2016 09:30:25
%S A086865 0,1,2,3,4,9,19,25,39,63,133,157,274,943,1009,1353,7297,16221,25256,
%T A086865 30424,52147
%N A086865 Numbers n such that 2*10^n+11 is prime.
%C A086865 a(22) > 10^5. - _Robert Price_, Jan 10 2015
%t A086865 Do[ If[ PrimeQ[2*10^n + 11], Print[n]], {n, 0, 4800}]
%o A086865 (PARI) is(n)=isprime(2*10^n+11) \\ _Charles R Greathouse IV_, Sep 27 2016
%Y A086865 Cf. A081677.
%K A086865 hard,more,nonn
%O A086865 1,3
%A A086865 _Carl R. White_, Aug 20 2003
%E A086865 Edited and extended by _Robert G. Wilson v_, Aug 25 2003
%E A086865 Term a(13) (had been listed as 254) corrected by _Jon E. Schoenfield_, Jul 13 2010
%E A086865 a(17)-a(21) from _Robert Price_, Jan 10 2015