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 A224506 #31 Mar 17 2024 02:17:05 %S A224506 2,70,88,6562,9100,11758,34334,39212,120590 %N A224506 Numbers k such that 9^k - k is prime. %C A224506 a(7) > 20000. - _Giovanni Resta_, Apr 09 2013 %C A224506 a(10) > 2*10^5. - _Robert Price_, Mar 12 2014 %t A224506 Select[Range[1000], PrimeQ[9^# - #] &] (* _Alonso del Arte_, Apr 11 2013 *) %o A224506 (PARI) is(n)=ispseudoprime(9^n-n) \\ _Charles R Greathouse IV_, Jun 13 2017 %Y A224506 Cf. A048744, A058037, A057908, A058046, A058829, A224470, A224471. %K A224506 nonn,more %O A224506 1,1 %A A224506 _Alex Ratushnyak_, Apr 08 2013 %E A224506 a(6) from _Giovanni Resta_, Apr 09 2013 %E A224506 a(7)-a(9) from _Robert Price_, Mar 12 2014