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Numbers k such that 4*k^4 + 3 is prime.
3

%I #12 Feb 10 2020 14:08:31

%S 0,1,2,5,11,16,47,49,52,53,68,73,77,86,91,115,128,140,143,166,170,182,

%T 206,220,224,229,263,271,278,284,287,340,341,353,359,362,380,382,388,

%U 395,401,403,413,415,427,437,476,497,506,515,523,598,611,619,625,647

%N Numbers k such that 4*k^4 + 3 is prime.

%H Daniel Starodubtsev, <a href="/A118660/b118660.txt">Table of n, a(n) for n = 1..10000</a>

%F A000040(t)=4*k^4+3 - _R. J. Mathar_, May 30 2006

%e If k=91 then 4*k^4 + 3 = 274299847 (prime).

%t Select[Range[0,700],PrimeQ[4#^4+3]&] (* _Harvey P. Dale_, Dec 06 2015 *)

%o (PARI) isA118660(n)= { if(isprime(4*n^4+3), return(1), return(0) ); } { for(n=0,6000, if(isA118660(n)==1, print1(n,",") ); ); } \\ _R. J. Mathar_, May 30 2006

%K nonn

%O 1,3

%A _Parthasarathy Nambi_, May 24 2006

%E More terms from _R. J. Mathar_, May 30 2006