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A303244
Number of 4Xn 0..1 arrays with every element equal to 0, 2, 3, 5 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.
1
8, 3, 55, 10, 255, 149, 1676, 3307, 18505, 65498, 290437, 1198777, 5087180, 21490967, 90839013, 384340750, 1625471539, 6876513885, 29091034026, 123070552817, 520674602677, 2202800218342, 9319394664521, 39427619066391, 166806435914930
OFFSET
1,1
COMMENTS
Row 4 of A303242.
FORMULA
Empirical recurrence of order 67 (see link above)
EXAMPLE
Some solutions for n=5
..0..1..0..1..0. .0..1..0..0..0. .0..0..0..1..1. .0..0..1..1..1
..1..1..1..1..1. .1..1..1..0..1. .1..0..1..1..1. .1..0..0..1..0
..1..1..0..0..0. .1..1..0..0..1. .1..0..0..1..0. .0..0..1..1..0
..1..1..1..0..0. .1..1..1..0..0. .0..0..0..1..0. .1..0..0..1..1
CROSSREFS
Cf. A303242.
Sequence in context: A256046 A197245 A302462 * A038281 A302370 A303086
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 20 2018
STATUS
approved