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A302164
Number of 2Xn 0..1 arrays with every element equal to 0, 1 or 3 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.
4
2, 3, 9, 17, 25, 65, 185, 385, 649, 1489, 3929, 8609, 15913, 34545, 85497, 191809, 377545, 802961, 1894553, 4279521, 8785769, 18612785, 42501945, 95817857, 202153993, 429672401, 960801241, 2153871393, 4621792425, 9879318897
OFFSET
1,1
COMMENTS
Row 2 of A302163.
LINKS
FORMULA
Empirical: a(n) = a(n-1) +16*a(n-4) -8*a(n-5) for n>6
EXAMPLE
Some solutions for n=5
..0..0..1..0..1. .0..1..1..0..1. .0..1..0..0..1. .0..1..0..1..0
..1..1..1..0..1. .0..1..0..1..1. .0..0..1..0..1. .0..1..0..0..1
CROSSREFS
Cf. A302163.
Sequence in context: A270339 A272057 A056658 * A295965 A034467 A234646
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 02 2018
STATUS
approved