%I #10 Sep 08 2022 08:46:07
%S 2,4,5,10,12,13,14,15,17,18,19,20,21,22,23,24,26,27,28,29,30,31,33,34,
%T 36,37,39,41,42,43,44,45,46,47,49,51,52,53,55,56,57,59,60,61,62,63,64,
%U 66,67,68,69,70,71,72,73,74,75,76,80,81,82,83,84,85,86,88
%N Numbers n such that (n+1)^7n^7 is not prime.
%H Vincenzo Librandi, <a href="/A241268/b241268.txt">Table of n, a(n) for n = 1..10000</a>
%e 4 is in this sequence because 5^7  4^7 = 61741 = 29*2129.
%t Select[Range[100], ! PrimeQ[(# + 1)^7  #^7] &]
%o (Magma) [n: n in [0..350]  not IsPrime((n+1)^7n^7)];
%Y Complement of A113826.
%K nonn,easy
%O 1,1
%A _Vincenzo Librandi_, Apr 20 2014
