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A115631 Triangle read by rows: row n (n>=2) gives a set of n primes with the property that the pairwise averages are all distinct primes, having the smallest largest element. 3

%I

%S 3,7,3,7,19,3,11,23,71,5,29,53,89,173,3,11,83,131,251,383,5,17,41,101,

%T 257,521,881,11,83,251,263,443,1103,1511,2111,257,269,509,857,1697,

%U 2309,2477,2609,5417,11,83,251,263,1511,2351,2963,7583,8663,10691

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

%C 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.

%C The table on page 6 of Granville is wrong. - _Arkadiusz Wesolowski_, Mar 11 2013

%H Toshitaka Suzuki, <a href="/A115631/b115631.txt">Table of n, a(n) for n = 2..91</a>

%H Andrew Granville, <a href="http://www.dms.umontreal.ca/~andrew/PDF/PrimePatterns.pdf">Prime number patterns</a>

%H Michel Marcus, <a href="/A115631/a115631.txt">Triangle read by rows</a>

%e The set of primes generated by {5, 29, 53, 89, 173} is {17, 29, 41, 47, 59, 71, 89, 101, 113, 131}.

%e Triangle begins:

%e 3, 7;

%e 3, 7, 19;

%e 3, 11, 23, 71;

%e 5, 29, 53, 89, 173;

%e 3, 11, 83, 131, 251, 383;

%e 5, 17, 41, 101, 257, 521, 881;

%e ...

%K nonn,tabf

%O 2,1

%A _T. D. Noe_, Jan 27 2006

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Last modified October 20 02:10 EDT 2019. Contains 328244 sequences. (Running on oeis4.)