|
|
A066179
|
|
Primes p such that (p-1)/2 and (p-3)/4 are also prime.
|
|
12
|
|
|
11, 23, 47, 167, 359, 719, 1439, 2039, 2879, 4079, 4127, 4919, 5639, 5807, 5927, 6047, 7247, 7559, 7607, 7727, 9839, 10799, 11279, 13799, 13967, 14159, 15287, 15647, 20327, 21599, 21767, 23399, 24407, 24527, 25799, 28319, 28607, 29399
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,1
|
|
COMMENTS
|
Call p "m-prime" iff (p-(2^i-1))/2^i is prime for i=0..m; sequence gives 2-primes. 0-primes are primes (A000040) and 1-primes are safe primes (A005385). a(n)-1 and a(n) are consecutive terms of the sequence A065966. It is not known if there are infinitely many m-primes for m > 0.
|
|
LINKS
|
|
|
MATHEMATICA
|
|
|
PROG
|
(PARI) { n=0; default(primelimit, 4294965247); for (m=1, 10^9, p=prime(m); if (frac((p-3)/4), next); if (isprime((p-3)/4) && isprime((p-1)/2), write("b066179.txt", n++, " ", p); if (n==1000, return)) ) } \\ Harry J. Smith, Feb 05 2010
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
EXTENSIONS
|
|
|
STATUS
|
approved
|
|
|
|