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A115349
Numbers k such that (4*k^5 + 1) is prime.
2
1, 12, 15, 19, 27, 40, 49, 57, 60, 90, 93, 102, 132, 133, 147, 148, 153, 177, 190, 219, 240, 249, 258, 265, 274, 277, 280, 294, 313, 324, 337, 342, 363, 382, 394, 435, 448, 453, 462, 483, 489, 502, 522, 534, 538, 550, 580, 588, 609, 613, 634, 643, 648, 649
OFFSET
1,2
LINKS
EXAMPLE
If k=90 then (4*90^5 + 1) = 23619600001, which is prime.
If k=133 then (4*133^5 + 1) = 166463183573, which is prime.
MAPLE
select(t -> isprime(4*t^5+1), [$1..1000]); # Robert Israel, Jun 19 2018
MATHEMATICA
Do[If[PrimeQ[4*n^5 + 1], Print[n]], {n, 0, 1000}]
Select[Range[700], PrimeQ[4#^5+1]&] (* Harvey P. Dale, Aug 25 2023 *)
PROG
(Magma) [n: n in [0..1500] | IsPrime(4*n^5 + 1)]; // Vincenzo Librandi, Jan 31 2011
(PARI) is(n)=isprime((4*n^5+1)) \\ Charles R Greathouse IV, Jun 13 2017
CROSSREFS
Sequence in context: A329731 A350563 A120169 * A196224 A163657 A117815
KEYWORD
nonn,easy
AUTHOR
Parthasarathy Nambi, Mar 07 2006
EXTENSIONS
More terms from Craig Baribault (csb166(AT)psu.edu), Mar 14 2006 and Jessica M. Cornwall (jmc510(AT)psu.edu), Mar 22 2006
STATUS
approved