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A318078
Number of nX4 0..1 arrays with every element unequal to 0, 1, 3 or 5 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.
1
5, 7, 11, 22, 34, 64, 132, 280, 556, 1083, 2208, 4480, 9083, 18324, 37073, 74864, 151386, 307006, 622583, 1259310, 2546594, 5156916, 10449815, 21161643, 42837534, 86725499, 175609679, 355607121, 720103580, 1458127803, 2952342256, 5977830149
OFFSET
1,1
COMMENTS
Column 4 of A318082.
LINKS
EXAMPLE
Some solutions for n=5
..0..1..1..1. .0..0..1..1. .0..0..0..1. .0..0..0..0. .0..0..0..0
..0..0..1..1. .0..0..0..1. .0..0..0..0. .0..0..1..0. .0..0..1..0
..0..0..0..1. .0..0..0..0. .1..0..0..0. .0..0..1..1. .1..1..0..0
..1..1..1..1. .1..0..0..0. .1..1..0..0. .0..1..0..0. .0..1..0..0
..0..1..1..1. .1..1..0..0. .1..1..1..0. .0..0..0..0. .0..0..0..0
CROSSREFS
Cf. A318082.
Sequence in context: A045441 A128841 A057733 * A174332 A248595 A266233
KEYWORD
nonn
AUTHOR
R. H. Hardin, Aug 15 2018
STATUS
approved