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%I #18 Nov 21 2013 12:47:47
%S 1,2,4,6,16,180,210,430,466,556,690,760,936,966,1150,1870,2266,2646,
%T 2676,3390,3516,3910,4006,4566,4590,4936,5086,6576,6970,8626,9276,
%U 9336,10006,13686,15510,17320,17550,17850,18040,18060,18586,18700,19380
%N Numbers n such that n+1, n^2+1 and n^4+1 are primes.
%H Charles R Greathouse IV, <a href="/A070325/b070325.txt">Table of n, a(n) for n = 1..10000</a>
%t Do[ If[ PrimeQ[n + 1] && PrimeQ[n^2 + 1] && PrimeQ[n^4 + 1], Print[n]], {n, 1, 20000}]
%t Select[Prime[Range[2200]]-1,And@@PrimeQ[{#^2+1,#^4+1}]&] (* _Harvey P. Dale_, Sep 24 2011 *)
%o (PARI) for(n=1,33000,if(isprime(n^2+1)*isprime(n^4+1)*isprime(n+1)==1,print1(n,",")))
%Y Subsequence of A070689. [Zak Seidov, Apr 09 2011]
%K easy,nonn
%O 1,2
%A _Benoit Cloitre_, May 11 2002
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