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%I #9 Sep 14 2017 04:05:17
%S 1,11,12,20,24,27,28,34,40,44,61,74,79,82,95,96,119,131,136,147,148,
%T 156,164,170,173,180,187,209,211,238,252,255,269,279,299,328,337,340,
%U 343,371,379,380,388,397,413,452,462,473,476,483,516,522,527,530,539,572
%N Numbers n such that (2n^2)^4 + 1 is prime.
%C Corresponding primes of the form (2n^2)^4 + 1 are {17, 3429742097, 6879707137, 409600000001, ...}.
%C There are consecutive twin pairs {a(n),a(n+1)} = {11,12}, {27,28}, {95,96},{147,148}, ...
%H G. C. Greubel, <a href="/A121979/b121979.txt">Table of n, a(n) for n = 1..5000</a>
%t Select[Range[1000],PrimeQ[(2*#1^2)^4+1]&]
%o (PARI) is(n)=isprime((2*n^2)^4+1) \\ _Charles R Greathouse IV_, Jun 13 2017
%Y Cf. A000068.
%K nonn,easy
%O 1,2
%A _Alexander Adamchuk_, Sep 10 2006
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