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

Author

T. D. Noe, Jan 27 2006

Keywords

• nonn
• tabf

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

Examples

			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;
...
		

Links

• Toshitaka Suzuki, Table of n, a(n) for n = 2..91
• Andrew Granville, Prime number patterns
• Michel Marcus, Triangle read by rows