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Triangle read by rows: n-th row is the smallest set of n numbers in arithmetic progression with the same prime signature.
8

%I #14 Jan 03 2020 10:17:18

%S 1,2,3,3,5,7,5,11,17,23,5,11,17,23,29,7,37,67,97,127,157,481,485,489,

%T 493,497,501,505,635,707,779,851,923,995,1067,1139,635,707,779,851,

%U 923,995,1067,1139,1211,199,409,619,829,1039,1249,1459,1669,1879,2089,3841

%N Triangle read by rows: n-th row is the smallest set of n numbers in arithmetic progression with the same prime signature.

%C In this sequence "smallest" means that the last term of the arithmetic progression is minimized. A113460 minimizes the first term.

%H <a href="/index/Pri#primes_AP">Index entries for sequences related to primes in arithmetic progressions</a>

%e Triangle begins:

%e 1

%e 2,3

%e 3,5,7

%e 5,11,17,23

%e 5,11,17,23,29

%e 7,37,67,97,127,157

%e 481,485,489,493,497,501,505

%e 635,707,779,851,923,995,1067,1139

%e 635,707,779,851,923,995,1067,1139,1211

%e 199,409,619,829,1039,1249,1459,1669,1879,2089

%e ...

%Y A087310 contains the corresponding common differences, A087308 the initial terms, A087309 the final terms.

%Y Cf. A087308, A087309, A087310, A114660, A114663, A114670.

%Y Row 10 is the same for A113470, A133276, A133277 and listed as A033168.

%K nonn,tabl

%O 1,2

%A _Amarnath Murthy_, Sep 02 2003

%E Edited and extended by _David Wasserman_, Jan 08 2006

%E Further edits by _N. J. A. Sloane_, Oct 17 2007