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A303964
Number of nX3 0..1 arrays with every element unequal to 0, 1, 3 or 5 king-move adjacent elements, with upper left element zero.
2
3, 9, 13, 26, 54, 101, 186, 361, 700, 1340, 2562, 4913, 9427, 18084, 34674, 66476, 127478, 244485, 468836, 899014, 1723966, 3305986, 6339698, 12157161, 23312919, 44705673, 85729179, 164397103, 315253197, 604539962, 1159286107, 2223085660
OFFSET
1,1
COMMENTS
Column 3 of A303969.
LINKS
FORMULA
Empirical: a(n) = a(n-1) +2*a(n-3) +2*a(n-4) +a(n-5) +a(n-6) -a(n-7) -a(n-11) -a(n-12)
EXAMPLE
Some solutions for n=5
..0..0..0. .0..0..0. .0..0..1. .0..0..0. .0..0..1. .0..1..1. .0..0..1
..0..0..1. .0..0..1. .0..1..1. .0..0..0. .0..0..0. .1..1..1. .0..0..0
..0..0..0. .0..1..1. .1..1..1. .1..0..0. .0..0..0. .1..1..1. .0..0..0
..0..0..0. .1..1..1. .1..1..1. .1..1..0. .0..0..1. .1..1..1. .0..0..0
..1..0..0. .1..1..1. .1..1..1. .1..1..1. .0..0..0. .1..1..1. .0..1..0
CROSSREFS
Cf. A303969.
Sequence in context: A113510 A163795 A079994 * A124825 A074938 A057260
KEYWORD
nonn
AUTHOR
R. H. Hardin, May 03 2018
STATUS
approved