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A133160
Numbers k such that k^3 + k + 91 is prime.
3
2, 6, 9, 11, 12, 17, 20, 23, 27, 29, 33, 38, 48, 50, 53, 59, 62, 68, 71, 75, 81, 87, 92, 93, 101, 114, 123, 129, 137, 152, 153, 170, 171, 176, 186, 197, 198, 222, 225, 246, 248, 254, 258, 263, 270, 284, 288, 293, 296, 297, 303, 306, 309, 314, 321, 324, 332, 335
OFFSET
1,1
LINKS
EXAMPLE
2 is in the sequence because 2^3+2+91 = 101 is prime.
93 is in the sequence because 93^3+93+91 = 804541 is prime.
MAPLE
a:=proc(n) if isprime(n^3+n+91)=true then n else end if end proc: seq(a(n), n =1..300); # Emeric Deutsch, Jan 08 2008
MATHEMATICA
Select[Range[400], PrimeQ[ #^3 + # + 91] &] (* Stefan Steinerberger, Dec 24 2007 *)
PROG
(Magma) [ n: n in [0..400] | IsPrime(n^3+n+91) ]; // Vincenzo Librandi, Jan 31 2011
(PARI) is(n)=isprime(n^3+n+91) \\ Charles R Greathouse IV, Jun 06 2017
CROSSREFS
Cf. A002837.
Sequence in context: A121248 A066586 A146974 * A128906 A192420 A139639
KEYWORD
nonn,easy
AUTHOR
Parthasarathy Nambi, Dec 17 2007
EXTENSIONS
More terms from Stefan Steinerberger, Dec 24 2007
STATUS
approved