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A230223
Primes p such that 3*p-4, 3*p-10, and 3*p-14 are all prime.
13
7, 11, 17, 19, 31, 37, 47, 59, 79, 107, 131, 151, 157, 229, 317, 367, 409, 431, 479, 499, 521, 541, 739, 787, 1031, 1181, 1307, 1381, 1487, 1601, 1697, 1747, 1951, 2551, 2749, 2767, 2917, 3251, 3391, 3449, 3581, 3931, 4217, 4349, 4447, 4567, 4639, 4721, 4909, 4967
OFFSET
1,1
COMMENTS
Conjecture: Any even number greater than 35 can be written as a sum of four terms of this sequence.
Primes in the sequence should be sparser than twin primes although this has not been proved.
LINKS
Zhi-Wei Sun, Conjectures involving primes and quadratic forms, preprint, arXiv:1211.1588.
EXAMPLE
a(1) = 7 since 3*7-4 = 17, 3*7-10 = 11 and 3*7-14 = 7 are prime.
MATHEMATICA
RQ[n_]:=n>5&&PrimeQ[3n-4]&&PrimeQ[3n-10]&&PrimeQ[3n-14]
m=0
Do[If[RQ[Prime[n]], m=m+1; Print[m, " ", Prime[n]]], {n, 1, 1000}]
Select[Prime[Range[700]], AllTrue[3#-{4, 10, 14}, PrimeQ]&] (* Harvey P. Dale, Sep 29 2023 *)
PROG
(PARI) is(p)=isprime(p) && isprime(3*p-4) && isprime(3*p-10) && isprime(3*p-14) \\ Charles R Greathouse IV, Oct 12 2013
KEYWORD
nonn
AUTHOR
Zhi-Wei Sun, Oct 12 2013
STATUS
approved