|
| |
|
|
A075322
|
|
Pair the odd primes so that the k-th pair is (p, p+2k) where p is the smallest prime not included earlier such that p and p+2k are primes and p+2k also does not occur earlier: (3, 5), (7, 11), (13, 19), (23, 31), (37, 47), (17, 29), ... This is the sequence of the second member of every pair.
|
|
2
| |
|
|
5, 11, 19, 31, 47, 29, 59, 71, 61, 73, 89, 103, 109, 127, 131, 139, 149, 173, 151, 197, 211, 223, 227, 239, 251, 281, 311, 97, 293, 307, 331, 263, 233, 313, 347, 359, 317, 241, 271, 419, 367, 421, 439, 461, 479, 443, 491, 379, 499, 449, 487, 521, 541, 523
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 1,1
|
|
|
COMMENTS
| Question: Is every prime p a member of some pair?
|
|
|
PROG
| (PARI) v=vector(10^5):for(n=1, 100, f=0:i=3:while(!f, while(v[i], i=nextprime(i+1)): if(isprime(i+2*n)&&!v[i+2*n], f=1:v[i]=1:v[i+2*n]=1:print1(i+2*n", "):break, i=i+1)))
|
|
|
CROSSREFS
| Equals A075321(n)+2n, also A075323(2n).
Sequence in context: A003147 A106068 A164566 * A079850 A065995 A023245
Adjacent sequences: A075319 A075320 A075321 * A075323 A075324 A075325
|
|
|
KEYWORD
| nonn
|
|
|
AUTHOR
| Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Sep 14 2002
|
|
|
EXTENSIONS
| More terms from Ralf Stephan (ralf(AT)ark.in-berlin.de), Mar 27 2003
|
| |
|
|
