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 A191568 #32 Apr 27 2022 02:28:31 %S A191568 1,2,3,9,10,14,33,36 %N A191568 Numbers k such that k*(k+1)^k+1 is prime. %C A191568 The corresponding primes are a subset of the generalized Cullen primes (A210339 U A050920). - _Jeppe Stig Nielsen_, Apr 12 2016 %e A191568 a(1)=1 because 1*2^1+1=3 is prime, a(2)=2 because 2*3^2+1=19 is prime, a(3)=3 because 3*4^3+1=193 is prime, a(4)=9 because 9*10^9+1=9000000001 is prime, a(5)=10 because 10*11^10+1=259374246011 is prime. %t A191568 Select[Range@ 100, PrimeQ[# (# + 1)^# + 1] &] (* _Michael De Vlieger_, Apr 12 2016 *) %o A191568 (PARI) is(n)=ispseudoprime(n*(n+1)^n+1) \\ _Charles R Greathouse IV_, Jun 13 2017 %Y A191568 Cf. A109618, A110709, A210339, A271718. %K A191568 nonn,hard,more %O A191568 1,2 %A A191568 _Juri-Stepan Gerasimov_, Jun 13 2011