%I A116542
%S A116542 1,2,2,6,8,6,12,16,16,12,72,432,2016,432,72,72,2784,23904,23904,2784,72,
%T A116542 864,35712,7102656,19611648,7102656,35712,864
%N A116542 Table B(m,n), read by antidiagonals, where B(m,n) is the number of ways
integers 1,..,m*n can be put into an m X n grid so that every adjacent
(NESW) pair of integers are coprime.
%C A116542 Sequence suggested by Leroy Quet on the SeqFan mailing list. B(1,n)=B(n,
1)=A076220(n).
%H A116542 Leroy Quet, <a href="http://www.prism-of-spirals.net/">Home Page</a>
(listed in lieu of email address)
%e A116542 The 16 configuration 3x2 are the following
%e A116542 ------------------------------------------------
%e A116542 1 2 3 | 2 5 6 | 3 4 1 | 4 5 6 | 6 1 2 | 6 5 4
%e A116542 6 5 4 | 3 4 1 | 2 5 6 | 3 2 1 | 5 4 3 | 1 2 3
%e A116542 ------------------------------------------------
%e A116542 1 4 3 | 3 2 1 | 3 4 5 | 5 2 3 | 6 1 4
%e A116542 6 5 2 | 4 5 6 | 2 1 6 | 6 1 4 | 5 2 3
%e A116542 ------------------------------------------------
%e A116542 2 1 6 | 3 2 5 | 4 1 6 | 5 4 3 | 6 5 2
%e A116542 3 4 5 | 4 1 6 | 3 2 5 | 6 1 2 | 1 4 3
%e A116542 ------------------------------------------------
%Y A116542 Cf. A076220.
%Y A116542 Sequence in context: A101343 A134457 A092522 this_sequence A142243 A091441
A099490
%Y A116542 Adjacent sequences: A116539 A116540 A116541 this_sequence A116543 A116544
A116545
%K A116542 nonn,tabl
%O A116542 1,2
%A A116542 Giovanni Resta (g.resta(AT)iit.cnr.it), Mar 28 2006
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