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%I #10 Mar 11 2018 03:47:13
%S 1,2,3,5,7,10,13,15,18
%N a(n) is the number of distances used by minimal prime-complete rulers for the first n primes.
%C The best known upper bounds for a(9-15) are 22, 25, 29, 33, 37, 41, 45. See attached file for the corresponding rulers. - _Dmitry Kamenetsky_, Mar 09 2018
%H Dmitry Kamenetsky, <a href="/A096221/a096221.txt">Upper bounds and their rulers for a(9-15)</a>
%H Carlos Rivera, <a href="http://www.primepuzzles.net/puzzles/puzz_172.htm">The Prime Puzzles & Problems Connection: Puzzle 172</a>.
%H Carlos Rivera, <a href="http://www.primepuzzles.net/puzzles/puzz_914.htm">The Prime Puzzles & Problems Connection: Puzzle 914</a>.
%e a(7)=15: there are 7 primes (2, 3, 5, 7, 11, 13, 17) and 8 ones. These rulers can generate every distance between 1 and 66, inclusive. There are two such rulers: 1.1.1.1.11.1.1.2.13.7.17.1.3.5.1 and 1.1.1.1.11.2.1.1.13.7.17.1.5.3.1
%K nonn,more
%O 0,2
%A _Ray G. Opao_, Jul 29 2004
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