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A251301
Number of (n+1) X (1+1) 0..3 arrays with no 2 X 2 subblock having the sum of its diagonal elements less than the maximum of its antidiagonal elements.
1
196, 2292, 26664, 310224, 3609989, 42010273, 488885832, 5689307216, 66208118088, 770483038240, 8966334130537, 104343825558858, 1214279300276685, 14130919690235492, 164445602628262220, 1913701076545003452
OFFSET
1,1
LINKS
FORMULA
Empirical: a(n) = 16*a(n-1) - 60*a(n-2) + 116*a(n-3) - 104*a(n-4) + 48*a(n-5) - 11*a(n-6) + a(n-7).
Empirical g.f.: x*(196 - 844*x + 1752*x^2 - 1616*x^3 + 757*x^4 - 175*x^5 + 16*x^6) / (1 - 16*x + 60*x^2 - 116*x^3 + 104*x^4 - 48*x^5 + 11*x^6 - x^7). - Colin Barker, Nov 28 2018
EXAMPLE
Some solutions for n=3:
..3..0....3..3....3..3....2..2....1..2....2..0....3..0....1..0....2..2....2..0
..2..2....2..1....2..0....2..2....3..2....3..1....0..1....2..2....3..1....3..1
..2..0....2..2....1..0....2..3....3..3....2..3....1..1....2..3....3..2....2..2
..3..3....2..3....1..1....2..1....2..1....3..3....2..2....2..3....1..1....0..2
CROSSREFS
Column 1 of A251308.
Sequence in context: A014798 A366278 A251308 * A277792 A178722 A061622
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 01 2014
STATUS
approved