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A253461
Number of (n+1) X (n+1) 0..2 arrays with every 2 X 2 subblock diagonal maximum minus antidiagonal minimum unequal to its neighbors horizontally, vertically, diagonally and antidiagonally.
1
81, 800, 2000, 3744, 8000, 12800, 32000, 59904, 128000, 204800, 512000, 958464, 2048000, 3276800, 8192000, 15335424, 32768000, 52428800, 131072000, 245366784, 524288000, 838860800, 2097152000, 3925868544, 8388608000, 13421772800
OFFSET
1,1
LINKS
FORMULA
Empirical: a(n) = 16*a(n-4) for n>5.
Empirical g.f.: x*(81 + 800*x + 2000*x^2 + 3744*x^3 + 6704*x^4) / ((1 - 2*x)*(1 + 2*x)*(1 + 4*x^2)). - Colin Barker, Dec 13 2018
EXAMPLE
Some solutions for n=4:
..0..0..1..0..2....0..2..1..1..2....1..2..0..2..1....2..0..2..0..2
..1..1..0..1..0....0..0..1..0..2....2..1..1..0..1....0..2..1..1..0
..1..1..2..1..2....1..1..0..1..0....1..2..0..1..1....1..1..2..0..1
..1..2..1..2..0....1..1..2..1..2....2..1..1..0..2....0..2..1..1..0
..1..0..2..2..2....1..2..1..2..1....2..2..1..0..0....2..2..1..1..1
CROSSREFS
Diagonal of A253468.
Sequence in context: A206086 A356534 A224002 * A247842 A273233 A045792
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 01 2015
STATUS
approved