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 A108468 #17 Sep 27 2024 14:26:48 %S A108468 1,2,8,10,20,590,1058 %N A108468 Numbers k such that (1/9)*(-1 + 10^k) + k is prime. %C A108468 Some of the larger entries may only correspond to probable primes. %C A108468 a(8) > 6000. - _Tyler NeSmith_, May 09 2021 %C A108468 a(8) > 10^5. - _Michael S. Branicky_, Sep 27 2024 %o A108468 (PARI) is(n)=ispseudoprime((10^n-1)/9+n) \\ _Charles R Greathouse IV_, Jun 13 2017 %Y A108468 Cf. A110369. %K A108468 more,nonn %O A108468 1,2 %A A108468 _Jason Earls_, Jul 25 2005