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A309381 Lucky primes k such that k+6 is also a lucky prime.

%I A309381 #12 Mar 03 2022 10:54:29
%S A309381 7,31,37,67,73,613,991,1087,1117,2467,3301,3307,3607,4561,4987,4993,
%T A309381 6367,6373,8263,8641,9643,10903,11827,11953,12373,12547,15187,15901,
%U A309381 17047,18043,19603,20353,21751,23671,25147,28837,31033,31231,37957,38707,38917,43201,44383,46021,49627
%N A309381 Lucky primes k such that k+6 is also a lucky prime.
%C A309381 A031157(k) for k such that A309334(k)=6.
%C A309381 The minimum gap between lucky primes (after the first) is 6.
%H A309381 Robert Israel, <a href="/A309381/b309381.txt">Table of n, a(n) for n = 1..1615</a>
%e A309381 37 and 37+6=43 are both lucky primes, so 37 is in the sequence.
%p A309381 N:= 10^5: # for terms <= N
%p A309381 L:= [seq(i,i=1..N+6,2)]:
%p A309381 for n from 2 while n < nops(L) do
%p A309381   r:= L[n];
%p A309381   L:= subsop(seq(r*i=NULL, i=1..nops(L)/r), L);
%p A309381 od:
%p A309381 L:= convert(select(isprime,L),set):
%p A309381 A:= L intersect map(`-`,L,6):
%p A309381 sort(convert(A,list));
%Y A309381 Cf. A031157, A309334.
%K A309381 nonn
%O A309381 1,1
%A A309381 _Robert Israel_, Jul 26 2019