A229165 - OEIS

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A229165

a(n) is the number of n X n matrices of 0's, 1's and -1's in which the entries in each row or column sum to 1 and there are no adjacent -1's or 1's in any row or column.

%I #18 Sep 27 2013 14:14:41

%S 1,2,7,104,7255,2280064,2708080414,13039886441460

%N a(n) is the number of n X n matrices of 0's, 1's and -1's in which the entries in each row or column sum to 1 and there are no adjacent -1's or 1's in any row or column.

%Y Cf. A005130 (Robbins numbers).

%Y Cf. A050204 (entries in each row or column sum to 1).

%K nonn,more

%O 1,2

%A _Eric W. Weisstein_, Sep 25 2013

%E Additional terms from _R. H. Hardin_, Sep 25 2013