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 A279648 Rows of the self-orthogonal Latin squares of order 7, lexicographically sorted. 5

%I

%S 1,2,3,4,5,6,7,3,4,2,5,6,7,1,4,7,6,3,1,2,5,6,1,5,7,2,4,3,2,5,7,6,3,1,

%T 4,7,3,1,2,4,5,6,5,6,4,1,7,3,2,1,2,3,4,5,6,7,3,4,2,5,6,7,1,5,1,6,7,3,

%U 4,2,6,7,1,3,2,5,4,2,5,4,6,7,1,3,7,3,5,1,4,2,6,4,6,7,2,1,3,5

%N Rows of the self-orthogonal Latin squares of order 7, lexicographically sorted.

%C An m X m Latin square consists of m sets of the numbers 1 to m arranged in such a way that no row or column contains the same number twice.

%C Two m X m Latin squares are orthogonal if no pair of corresponding elements occurs more than once.

%C A self-orthogonal Latin square is a Latin square that is orthogonal to its transpose.

%C There are 19353600 self-orthogonal Latin squares of order 7.

%H Colin Barker, <a href="/A279648/b279648.txt">Table of n, a(n) for n = 1..500</a>

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/LatinSquare.html">Latin square</a>

%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Latin_square">Latin square</a>

%e The first four squares are:

%e 1 2 3 4 5 6 7 1 2 3 4 5 6 7 1 2 3 4 5 6 7 1 2 3 4 5 6 7

%e 3 4 2 5 6 7 1 3 4 2 5 6 7 1 3 4 2 5 6 7 1 3 4 2 5 6 7 1

%e 4 7 6 3 1 2 5 5 1 6 7 3 4 2 5 7 6 1 3 2 4 5 7 6 1 3 2 4

%e 6 1 5 7 2 4 3 6 7 1 3 2 5 4 6 1 7 2 4 3 5 6 1 7 3 2 4 5

%e 2 5 7 6 3 1 4 2 5 4 6 7 1 3 2 5 1 3 7 4 6 2 5 4 6 7 1 3

%e 7 3 1 2 4 5 6 7 3 5 1 4 2 6 7 3 4 6 1 5 2 7 3 1 2 4 5 6

%e 5 6 4 1 7 3 2 4 6 7 2 1 3 5 4 6 5 7 2 1 3 4 6 5 7 1 3 2

%Y Cf. A160368, A279649, A279650, A279849, A279850.

%K nonn,fini,tabf

%O 1,2

%A _Colin Barker_, Dec 16 2016

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Last modified May 21 15:12 EDT 2019. Contains 323444 sequences. (Running on oeis4.)