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 A271718 #6 Apr 12 2016 23:55:35 %S A271718 2,3,7,14,43,81,943,1621 %N A271718 Numbers n such that n*(n+1)^n - 1 is prime. %C A271718 The corresponding primes are a subset of the generalized Woodall primes (A210340). %e A271718 14 is a member because 14*15^14 - 1 = 408700964355468749 is a prime number. %t A271718 Select[Range[10^3], PrimeQ[# (# + 1)^# - 1] &] (* _Michael De Vlieger_, Apr 12 2016 *) %o A271718 (PARI) for(n=1,10^10,ispseudoprime(n*(n+1)^n-1)&&print1(n,", ")) %Y A271718 Cf. A191568, A210340. %K A271718 nonn,hard,more %O A271718 1,1 %A A271718 _Jeppe Stig Nielsen_, Apr 12 2016