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A257443
Number of (n+2) X (4+2) 0..1 arrays with no 3 x 3 subblock diagonal sum 0 and no antidiagonal sum 3 and no row sum 1 and no column sum 1.
1
49, 51, 59, 71, 89, 116, 155, 212, 296, 419, 599, 863, 1250, 1817, 2648, 3866, 5651, 8267, 12101, 17720, 25955, 38024, 55712, 81635, 119627, 175307, 256910, 376505, 551780, 808658, 1185131, 1736879, 2545505, 3730604, 5467451, 8012924, 11743496
OFFSET
1,1
LINKS
FORMULA
Empirical: a(n) = 2*a(n-1) - a(n-2) + a(n-3) - a(n-4) for n>6.
Empirical g.f.: x*(49 - 47*x + 6*x^2 - 45*x^3 + 4*x^4 + x^5) / ((1 - x)*(1 - x - x^3)). - Colin Barker, Dec 21 2018
EXAMPLE
Some solutions for n=4:
..0..0..0..0..0..0....0..1..1..0..1..1....1..1..0..1..1..1....0..0..0..0..0..0
..1..1..0..1..1..0....0..0..0..0..0..0....1..1..0..1..1..1....1..1..0..1..1..0
..1..1..0..1..1..0....0..1..1..0..1..1....0..0..0..0..0..0....1..1..0..1..1..0
..1..1..0..1..1..0....0..1..1..0..1..1....1..1..0..1..1..1....1..1..0..1..1..0
..0..0..0..0..0..0....0..1..1..0..1..1....1..1..0..1..1..1....1..1..0..1..1..0
..1..1..0..1..1..0....0..0..0..0..0..0....0..0..0..0..0..0....1..1..0..1..1..0
CROSSREFS
Column 4 of A257447.
Sequence in context: A176309 A080201 A042199 * A020276 A346805 A118073
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 23 2015
STATUS
approved