OFFSET
1,1
COMMENTS
From Weber, p. 15.
LINKS
Charles R Greathouse IV, Table of n, a(n) for n = 1..10000
H. J. Weber, Regularities of Twin, Triplet and Multiplet Prime Numbers, Mar 2, 2011.
EXAMPLE
a(1) = 11 because x^2 + x + 11 generates 0^2 + 0 + 11; 1^2 + 1 + 11 = 13; 2^2 + 2 + 11 = 17; 3^2 + 3 + 11 = 23; 4^2 + 4 + 11 = 31, all primes.
MATHEMATICA
okQ[n_] := And @@ PrimeQ[Table[i^2 + i + n, {i, 0, 4}]]; Select[Range[10000], okQ] (* T. D. Noe, Mar 03 2011 *)
Select[Prime[Range[12500]], AllTrue[#+{2, 6, 12, 20}, PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Aug 11 2019 *)
PROG
(PARI) forprime(p=2, 1e4, if(isprime(p+2)&&isprime(p+6)&&isprime(p+12) &&isprime(p+20), print1(p", "))) \\ Charles R Greathouse IV, Mar 04 2012
CROSSREFS
KEYWORD
nonn
AUTHOR
Jonathan Vos Post, Mar 03 2011
STATUS
approved