The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 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 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

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

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