

A230217


List of those primes p with p + 6 and 3*p + 8 also prime.


6



5, 7, 11, 13, 17, 31, 41, 47, 53, 61, 73, 83, 101, 103, 131, 151, 157, 167, 193, 223, 251, 263, 271, 277, 307, 311, 347, 367, 433, 563, 571, 593, 601, 613, 641, 647, 677, 733, 823, 857, 977, 1097, 1117, 1217, 1223, 1231, 1291, 1301, 1361, 1427
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OFFSET

1,1


COMMENTS

Clearly, no term is congruent to 4 modulo 5.
This sequence is interesting because of the conjecture in the comments in A230219.


LINKS

ZhiWei Sun, Table of n, a(n) for n = 1..10000


EXAMPLE

a(1) = 5 since neither 2 + 6 nor 3 + 6 is prime, but 5 + 6 = 11 and 3*5 + 8 = 23 are both prime.


MATHEMATICA

PQ[p_]:=PrimeQ[p+6]&&PrimeQ[3p+8]
m=0
Do[If[PQ[Prime[n]], m=m+1; Print[m, " ", Prime[n]]], {n, 1, 225}]


CROSSREFS

Cf. A023201, A230219.
Sequence in context: A227576 A114262 A255229 * A317250 A007529 A287956
Adjacent sequences: A230214 A230215 A230216 * A230218 A230219 A230220


KEYWORD

nonn


AUTHOR

ZhiWei Sun, Oct 11 2013


STATUS

approved



