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 A052289 #17 Nov 03 2021 21:28:47 %S A052289 0,2,4,12,18,36 %N A052289 Numbers n such that n!*2^n + n + 1 = A000165(n) + n + 1 is prime. %C A052289 For comparison, A000165(n)+1 is prime for n = 0, 1, 259, 16708, 18655,... (A256594). %C A052289 a(6) > 25000, if it exists. - _Giovanni Resta_, Jun 01 2018 %e A052289 n=4, 2^4*4! + 4 + 1 = 389 is prime. %t A052289 Select[Range[100], PrimeQ[#! 2^# + # + 1] &] (* _Giovanni Resta_, May 31 2018 *) %Y A052289 Cf. A000165, A052290, A256594. %K A052289 nonn,more %O A052289 1,2 %A A052289 _Labos Elemer_, Feb 08 2000 %E A052289 a(1)=0 inserted by _Sean A. Irvine_, Nov 03 2021