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 A105975 #11 Jun 16 2018 22:16:08
%S A105975 199,499,599,919,929,991,997,1999,2999,4999,8999,9199,9929,9949,49999,
%T A105975 59999,79999,94999,98999,99929,99989,99991,199999,599999,799999,
%U A105975 989999,991999,999199,999499,999599,999959,999979,2999999,4999999,9899999
%N A105975 Near-repdigit primes with 9 as repeated digit.
%H A105975 Harvey P. Dale, <a href="/A105975/b105975.txt">Table of n, a(n) for n = 1..1000</a>
%H A105975 Brady Haran and Simon Pampena, <a href="https://www.youtube.com/watch?v=HPfAnX5blO0">Glitch Primes and Cyclops Numbers</a>, Numberphile video (2015)
%e A105975 a(2)=499 is a term because all digits are equal to 9 except one.
%t A105975 Sort[Select[Flatten[Table[FromDigits/@(Flatten[Permutations/@Table[ Join[{n},PadRight[{},i,9]],{n,{1,2,4,5,7,8}}],1]),{i,2,6}]],PrimeQ]] (* _Harvey P. Dale_, May 07 2015 *)
%K A105975 base,nonn
%O A105975 1,1
%A A105975 _Shyam Sunder Gupta_, Apr 29 2005