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Number of permutations of 0..floor((5*n-2)/2) on odd squares of an 5Xn array such that each row, column, diagonal and (downwards) antidiagonal of odd squares is increasing
0

%I #5 Aug 25 2012 05:54:28

%S 1,1,1,4,20,189,1642,26451,307874,7027942,98057806,2850280812,

%T 44974137856

%N Number of permutations of 0..floor((5*n-2)/2) on odd squares of an 5Xn array such that each row, column, diagonal and (downwards) antidiagonal of odd squares is increasing

%C Row 5 of A215870

%e Some solutions for n=5

%e ..x..0..x..2..x....x..0..x..1..x....x..0..x..1..x....x..0..x..2..x

%e ..1..x..3..x..5....2..x..3..x..5....2..x..3..x..5....1..x..3..x..5

%e ..x..4..x..7..x....x..4..x..7..x....x..4..x..6..x....x..4..x..6..x

%e ..6..x..8..x..9....6..x..8..x.10....7..x..8..x.10....7..x..8..x..9

%e ..x.10..x.11..x....x..9..x.11..x....x..9..x.11..x....x.10..x.11..x

%K nonn

%O 1,4

%A _R. H. Hardin_ Aug 25 2012