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%I #6 Dec 15 2017 23:20:15
%S 1,2,5,6,69,131,426,1665,2129,2696,5250,7929,9689,13545,14154,14286,
%T 16434,19760,25739,27809,29631,36821,41819,46619,48321,59030,60500,
%U 61955,62321,73610,77685,79646,80535,82655,85251,86996,91014,96566,97739,105939,108240
%N Numbers n such that n^1+n+1, n^2+n+1, n^3+n+1 and n^4+n+1 are all prime.
%H Robert Israel, <a href="/A219117/b219117.txt">Table of n, a(n) for n = 1..1000</a>
%p select(t -> andmap(isprime, [2*t+1,t^2+t+1,t^3+t+1,t^4+t+1]), [$1..2*10^5]); # _Robert Israel_, Dec 15 2017
%o (Haskell)
%o a219117_list = filter (all (== 1) . p) [1..] where
%o p x = map (a010051 . (+ (x + 1)) . (x ^)) [1..4]
%Y Cf. A057683 (subsequence); A010051.
%K nonn
%O 1,2
%A _Reinhard Zumkeller_, Nov 12 2012
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