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Hilltop maps: number of n X n binary arrays indicating the locations of corresponding elements not exceeded by any horizontal, vertical or antidiagonal neighbor in a random 0..2 n X n array
0

%I #5 Dec 18 2015 18:18:14

%S 1,15,497,63309,32362849,66220959971,542011629493301,

%T 17745059393526510913,2323828045898042282454885

%N Hilltop maps: number of n X n binary arrays indicating the locations of corresponding elements not exceeded by any horizontal, vertical or antidiagonal neighbor in a random 0..2 n X n array

%C Diagonal of A218233

%e Some solutions for n=3

%e ..1..1..1....1..0..1....0..1..1....1..0..1....0..1..0....1..1..1....1..0..1

%e ..0..0..1....0..0..1....1..0..0....0..0..0....0..0..0....1..1..1....0..0..1

%e ..1..0..1....1..0..1....0..1..0....1..0..1....0..0..1....0..0..1....0..0..1

%K nonn

%O 1,2

%A _R. H. Hardin_ Oct 24 2012