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A253151
Number of (n+1)X(n+1) 0..1 arrays with every 2X2 subblock diagonal minus antidiagonal sum nondecreasing horizontally and vertically
0
16, 72, 94, 164, 308, 596, 1172, 2324, 4628, 9236, 18452, 36884, 73748, 147476, 294932, 589844, 1179668, 2359316, 4718612, 9437204, 18874388, 37748756, 75497492, 150994964, 301989908, 603979796
OFFSET
1,1
COMMENTS
Diagonal of A253159
FORMULA
Empirical: a(n) = 3*a(n-1) -2*a(n-2) for n>5
Empirical: a(n) = 18*2^(n-1) + 20 for n>3
EXAMPLE
Some solutions for n=6
..0..0..0..0..0..0..0....0..1..0..1..1..0..0....0..1..1..1..0..0..0
..1..1..1..1..1..1..1....1..1..0..1..1..0..0....0..1..1..1..0..0..0
..0..0..0..0..0..0..0....1..1..0..1..1..0..0....0..1..1..1..0..0..0
..1..1..1..1..1..1..1....1..1..0..1..1..0..0....0..1..1..1..0..0..0
..0..0..0..0..0..0..0....1..1..0..1..1..0..0....0..1..1..1..0..0..0
..0..0..0..0..0..0..0....1..1..0..1..1..0..0....0..1..1..1..0..0..0
..0..0..0..0..0..0..1....1..1..0..1..1..0..1....0..1..1..1..0..0..0
CROSSREFS
Sequence in context: A272964 A232579 A212862 * A339993 A232402 A212513
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 28 2014
STATUS
approved