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A075898 Numbers n such that 3^n + n^2 is prime. 1
2, 4, 10, 22, 40, 304, 1582, 3602 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(9) > 20000. - Jon E. Schoenfield, Jan 14 2015

LINKS

Table of n, a(n) for n=1..8.

MATHEMATICA

Select[Range[10000], PrimeQ[3^# + #^2] &] (* Vincenzo Librandi, Oct 04 2012 *)

PROG

(MAGMA)[n: n in [0..1000] | IsPrime(3^n+n^2)]; // Vincenzo Librandi, Dec 16 2010

(PARI) is(n)=ispseudoprime(3^n+n^2) \\ Charles R Greathouse IV, Jun 12 2017

CROSSREFS

Cf. A075899 (for the corresponding primes).

Sequence in context: A023036 A263661 A005306 * A274313 A291397 A091618

Adjacent sequences:  A075895 A075896 A075897 * A075899 A075900 A075901

KEYWORD

nonn,more

AUTHOR

Zak Seidov, Oct 17 2002

EXTENSIONS

a(6) from Vincenzo Librandi, Dec 16 2010

a(7) from D. S. McNeil, Dec 16 2010

a(8) from Vincenzo Librandi, Oct 04 2012

STATUS

approved

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Last modified August 22 12:09 EDT 2019. Contains 326177 sequences. (Running on oeis4.)