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A298179
Number of nX4 0..1 arrays with every element equal to 3, 5, 6 or 8 king-move adjacent elements, with upper left element zero.
1
0, 2, 2, 3, 6, 10, 15, 26, 44, 71, 118, 198, 327, 542, 904, 1503, 2498, 4162, 6935, 11554, 19268, 32151, 53662, 89614, 149735, 250294, 418576, 700335, 1172266, 1963050, 3288695, 5511834, 9241516, 15501095, 26010534, 43661526, 73317447, 123160206
OFFSET
1,2
COMMENTS
Column 4 of A298183.
LINKS
FORMULA
Empirical: a(n) = 2*a(n-1) +a(n-3) -2*a(n-4) -2*a(n-5)
EXAMPLE
Some solutions for n=7
..0..0..1..1. .0..0..1..1. .0..0..1..1. .0..0..1..1. .0..0..0..0
..0..0..1..1. .0..0..1..1. .0..0..1..1. .0..0..1..1. .0..0..0..0
..0..0..1..1. .0..0..1..1. .0..0..0..0. .0..0..1..1. .0..0..0..0
..0..0..1..1. .0..0..0..0. .1..1..0..0. .0..0..1..1. .0..0..0..0
..1..1..1..1. .1..1..0..0. .1..1..0..0. .0..0..1..1. .0..0..0..0
..1..1..0..0. .1..1..0..0. .1..1..0..0. .0..0..1..1. .1..1..1..1
..1..1..0..0. .1..1..0..0. .1..1..0..0. .0..0..1..1. .1..1..1..1
CROSSREFS
Cf. A298183.
Sequence in context: A137216 A369424 A070550 * A185084 A145778 A102762
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 14 2018
STATUS
approved