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 A242200 #13 Sep 08 2022 08:46:08 %S A242200 2,18,68,84,3812,14838,51582 %N A242200 Numbers n such that n*7^n - 1 is prime. %H A242200 Steven Harvey, <a href="http://harvey563.tripod.com/GeneralizedWoodallPrimes.txt">Generalized Woodall Search</a> %t A242200 Select[Range[2000], PrimeQ[# 7^# - 1] &] %o A242200 (Magma) [n: n in [0..3000] | IsPrime(n*7^n-1)]; %o A242200 (PARI) is(n)=ispseudoprime(n*7^n-1) \\ _Charles R Greathouse IV_, May 22 2017 %Y A242200 Cf. numbers n such that n*k^n - 1 is prime. A002234 (k=2), A006553 (k=3), A086661 (k=4), A059676 (k=5), A059675 (k=6), this sequence (k=7), A242201 (k=8), A242202 (k=9), A059671 (k=10). %K A242200 nonn,more %O A242200 1,1 %A A242200 _Vincenzo Librandi_, May 09 2014 %E A242200 a(5) - a(7) from Harvey's list (see Links).