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A115449
Numbers n such that 4*n^5 - 1 is prime.
0
1, 2, 3, 8, 12, 23, 27, 42, 68, 75, 86, 96, 113, 117, 125, 135, 140, 146, 168, 182, 185, 188, 191, 198, 233, 245, 255, 267, 281, 287, 297, 306, 311, 318, 327, 360, 362, 366, 377, 390, 392, 395, 408, 416, 423, 432, 447, 456, 465, 486, 488, 497, 516, 531, 555
OFFSET
1,2
EXAMPLE
If n=96 then (4*n^5 - 1) = 32614907903 (prime).
MATHEMATICA
Select[Range[500], PrimeQ[4*#^5 - 1] &] (* Stefan Steinerberger, Mar 09 2006 *)
PROG
(PARI) for(i=1, 2000, if(isprime(4*i^5-1), print1(i, ", "))) \\ Matthew Conroy, Mar 12 2006
(PARI) for(i=1, 2000, if(isprime(4*i^5-1), print1(i, ", "))) \\ Matthew Conroy, Mar 12 2006
CROSSREFS
Sequence in context: A249367 A257999 A350440 * A303851 A218542 A194452
KEYWORD
nonn
AUTHOR
Parthasarathy Nambi, Mar 08 2006
EXTENSIONS
More terms from Stefan Steinerberger, Zak Seidov and Matthew Conroy, Mar 12 2006
More terms from Matthew Conroy, Mar 12 2006
STATUS
approved