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%I #16 Aug 25 2023 14:52:35
%S 1,12,15,19,27,40,49,57,60,90,93,102,132,133,147,148,153,177,190,219,
%T 240,249,258,265,274,277,280,294,313,324,337,342,363,382,394,435,448,
%U 453,462,483,489,502,522,534,538,550,580,588,609,613,634,643,648,649
%N Numbers k such that (4*k^5 + 1) is prime.
%H Robert Israel, <a href="/A115349/b115349.txt">Table of n, a(n) for n = 1..10000</a>
%e If k=90 then (4*90^5 + 1) = 23619600001, which is prime.
%e If k=133 then (4*133^5 + 1) = 166463183573, which is prime.
%p select(t -> isprime(4*t^5+1), [$1..1000]); # _Robert Israel_, Jun 19 2018
%t Do[If[PrimeQ[4*n^5 + 1], Print[n]], {n, 0, 1000}]
%t Select[Range[700],PrimeQ[4#^5+1]&] (* _Harvey P. Dale_, Aug 25 2023 *)
%o (Magma) [n: n in [0..1500] | IsPrime(4*n^5 + 1)]; // _Vincenzo Librandi_, Jan 31 2011
%o (PARI) is(n)=isprime((4*n^5+1)) \\ _Charles R Greathouse IV_, Jun 13 2017
%Y Cf. A115104, A001912.
%K nonn,easy
%O 1,2
%A _Parthasarathy Nambi_, Mar 07 2006
%E More terms from Craig Baribault (csb166(AT)psu.edu), Mar 14 2006 and Jessica M. Cornwall (jmc510(AT)psu.edu), Mar 22 2006
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