OFFSET
1,1
REFERENCES
J. Matousek and J. Nesetril: Diskrete Mathematik: eine Entdeckungsreise, Springer-Lehrbuch, 2. Aufl., Berlin, 2007
LINKS
Zak Seidov, Table of n, a(n) for n = 1..3000
EXAMPLE
4^2 - 13 = 3 = prime(2), 4^2 + 13 = 29 = prime(10).
12^2 - 13 = 131 = prime(32), 12^2 + 13 = 157 = prime(37).
p = 948^2 - 13 = 898691 = prime(71194), q = prime(71195), first case that p and q are consecutive primes.
MAPLE
with(numtheory): A248785:=n->`if`(isprime(n^2-13) and isprime(n^2+13), n, NULL): seq(A248785(n), n=1..10^4); # Wesley Ivan Hurt, Oct 13 2014
MATHEMATICA
Select[Range[5000], AllTrue[#^2+{13, -13}, PrimeQ]&] (* Harvey P. Dale, May 28 2024 *)
PROG
(Magma) [n: n in [4..1000]| IsPrime(n^2-13) and IsPrime(n^2+13)] // Vincenzo Librandi, Nov 30 2010
CROSSREFS
KEYWORD
nonn
AUTHOR
Eva-Maria Zschorn (e-m.zschorn(AT)zaschendorf.km3.de), May 14 2010
EXTENSIONS
More terms from Vincenzo Librandi, May 16 2010
STATUS
approved