A115631 Triangle read by rows: row n (n>=2) gives a set of n primes such that the pairwise averages are all distinct primes, having the smallest largest element.

3, 7, 3, 7, 19, 3, 11, 23, 71, 5, 29, 53, 89, 173, 3, 11, 83, 131, 251, 383, 5, 17, 41, 101, 257, 521, 881, 11, 83, 251, 263, 443, 1103, 1511, 2111, 257, 269, 509, 857, 1697, 2309, 2477, 2609, 5417, 11, 83, 251, 263, 1511, 2351, 2963, 7583, 8663, 10691

Offset

2,1

Comments

This table is the same as A113832 for rows 2,3,4,6,12 and 13. Note that row 7, {5,17,41,101,257,521,881}, is the same as row 8 of A113832 with 761 deleted.

The table on page 6 of Granville is wrong. - Arkadiusz Wesolowski, Mar 11 2013

Links

Toshitaka Suzuki, Table of n, a(n) for n = 2..91

Andrew Granville, Prime number patterns

Michel Marcus, Triangle read by rows

Example

The set of primes generated by {5, 29, 53, 89, 173} is {17, 29, 41, 47, 59, 71, 89, 101, 113, 131}.
Triangle begins:
3, 7;
3, 7, 19;
3, 11, 23, 71;
5, 29, 53, 89, 173;
3, 11, 83, 131, 251, 383;
5, 17, 41, 101, 257, 521, 881;
...

Crossrefs

Sequence in context: A120124 A151573 A113832 * A053008 A053010 A118452

Adjacent sequences: A115628 A115629 A115630 * A115632 A115633 A115634

Keyword

nonn,tabf

Author

T. D. Noe, Jan 27 2006

Status

approved