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A253465
Number of (n+1) X (4+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
24208, 3072, 2600, 3744, 7496, 8272, 15680, 31824, 94016, 104272, 224960, 481104, 1478336, 1640272, 3573440, 7669584, 23627456, 26216272, 57149120, 122685264, 378013376, 419432272, 914360000, 1962936144, 6048188096, 6710888272
OFFSET
1,1
LINKS
FORMULA
Empirical: a(n) = a(n-2) + 16*a(n-4) - 16*a(n-6) for n>8.
Empirical g.f.: 8*x*(3026 + 384*x - 2701*x^2 + 84*x^3 - 47804*x^4 - 5578*x^5 + 44239*x^6 + 1600*x^7) / ((1 - x)*(1 + x)*(1 - 2*x)*(1 + 2*x)*(1 + 4*x^2)). - Colin Barker, Dec 14 2018
EXAMPLE
Some solutions for n=4:
..1..1..1..1..1....0..2..0..0..1....1..0..1..2..2....1..0..1..0..2
..0..1..1..2..0....0..0..1..0..2....0..1..1..2..0....1..2..1..2..2
..1..0..2..1..1....0..1..0..1..0....1..0..2..1..1....2..1..2..1..2
..0..1..1..2..0....2..1..2..1..2....0..1..1..2..0....0..1..0..1..1
..1..0..2..1..2....1..2..1..2..1....2..0..2..0..0....1..0..1..0..0
CROSSREFS
Column 4 of A253468.
Sequence in context: A234165 A321063 A309018 * A251154 A078870 A154069
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 01 2015
STATUS
approved