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A309381 Lucky primes k such that k+6 is also a lucky prime. 0
7, 31, 37, 67, 73, 613, 991, 1087, 1117, 2467, 3301, 3307, 3607, 4561, 4987, 4993, 6367, 6373, 8263, 8641, 9643, 10903, 11827, 11953, 12373, 12547, 15187, 15901, 17047, 18043, 19603, 20353, 21751, 23671, 25147, 28837, 31033, 31231, 37957, 38707, 38917, 43201, 44383, 46021, 49627 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

A031157(k) for k such that A309334(k)=6.

The minimum gap between lucky primes (after the first) is 6.

LINKS

Table of n, a(n) for n=1..45.

EXAMPLE

37 and 37+6=43 are both lucky primes, so 37 is in the sequence.

MAPLE

N:= 10^5: # for terms <= N

L:= [seq(i, i=1..N+6, 2)]:

for n from 2 while n < nops(L) do

  r:= L[n];

  L:= subsop(seq(r*i=NULL, i=1..nops(L)/r), L);

od:

L:= convert(select(isprime, L), set):

A:= L intersect map(`-`, L, 6):

sort(convert(A, list));

CROSSREFS

Cf. A031157, A309334.

Sequence in context: A238664 A272201 A325423 * A276741 A000696 A171733

Adjacent sequences:  A309378 A309379 A309380 * A309382 A309383 A309384

KEYWORD

nonn

AUTHOR

Robert Israel, Jul 26 2019

STATUS

approved

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Last modified May 8 05:46 EDT 2021. Contains 343653 sequences. (Running on oeis4.)