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 A062580 #18 Jul 04 2021 08:24:32 %S A062580 3,11,83,461,659,1129,3797,83869 %N A062580 Numbers k such that 14^k - 13^k is prime. %C A062580 Terms greater than 1000 may correspond to (unproven) strong pseudoprimes. %o A062580 (PARI) is(n)=ispseudoprime(14^n-13^n) \\ _Charles R Greathouse IV_, Jun 13 2017 %Y A062580 Cf. A000043, A057468, A059801, A059802, A062572-A062666. %K A062580 nonn,hard,more %O A062580 1,1 %A A062580 _Mike Oakes_, May 18 2001, May 19 2001 %E A062580 83869 found from _Jean-Louis Charton_, Sep 02 2009 %E A062580 Edited by _M. F. Hasler_, Sep 16 2013