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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 (list; graph; refs; listen; history; text; internal format)
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
CROSSREFS
Sequence in context: A155048 A296926 A063639 * A309587 A339954 A260893
KEYWORD
nonn
AUTHOR
Zhi-Wei Sun, Oct 12 2013
STATUS
approved

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Last modified April 18 20:26 EDT 2024. Contains 371781 sequences. (Running on oeis4.)