|
Search: id:A113875
|
|
|
| A113875 |
|
Slowest growing sequence of primes having the prime-pairwise-average property: if i<j, (a(i)+a(j))/2 is prime. |
|
+0
4
|
|
| 3, 7, 19, 139, 859, 8179, 173059, 1026199, 1827139, 15828679, 13187242759, 18732483199, 912492556939
(list; graph; listen)
|
|
|
OFFSET
|
1,1
|
|
|
COMMENT
|
Assuming the prime k-tuples conjecture, Granville shows (in section 2.4) that this sequence is infinite.
|
|
LINKS
|
Andrew Granville, Prime number patterns
|
|
EXAMPLE
|
The pairwise averages of {3,7,19} are the primes {5,11,13}.
|
|
MATHEMATICA
|
s={3, 7}; i=5; Do[While[ !And@@PrimeQ[(s+Prime[i])/2], i++ ]; AppendTo[s, Prime[i]]; i++, {n, 3, 10}]; s
|
|
CROSSREFS
|
Cf. A113832, A115760.
Adjacent sequences: A113872 A113873 A113874 this_sequence A113876 A113877 A113878
Sequence in context: A128024 A075487 A118128 this_sequence A111974 A066315 A058499
|
|
KEYWORD
|
hard,nonn
|
|
AUTHOR
|
T. D. Noe (noe(AT)sspectra.com), Jan 26 2006
|
|
EXTENSIONS
|
More terms from Don Reble (djr(AT)nk.ca) and Giovanni Resta (g.resta(AT)iit.cnr.it), Feb 15 2006
|
|
|
Search completed in 0.002 seconds
|
