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A296947
Number of nX3 0..1 arrays with each 1 adjacent to 1, 3 or 5 king-move neighboring 1s.
1
3, 16, 45, 135, 544, 1765, 5763, 20811, 70207, 236330, 822902, 2806042, 9547539, 32855983, 112351535, 383730987, 1315580367, 4501742568, 15396061261, 52720880494, 180431027632, 617365998304, 2113260768118, 7232567686580
OFFSET
1,1
COMMENTS
Column 3 of A296952.
LINKS
FORMULA
Empirical: a(n) = 3*a(n-1) +a(n-2) +16*a(n-3) -46*a(n-4) -20*a(n-5) -19*a(n-6) +148*a(n-7) +64*a(n-8) -58*a(n-9) -180*a(n-10) +9*a(n-11) +70*a(n-12) +35*a(n-13) -29*a(n-14) -13*a(n-15) +7*a(n-16) +6*a(n-17) +a(n-18) -2*a(n-19)
EXAMPLE
Some solutions for n=7
..0..0..0. .1..0..0. .1..1..1. .0..0..0. .0..1..1. .0..0..0. .0..0..0
..1..1..0. .1..0..1. .1..1..1. .0..0..1. .0..1..1. .1..0..1. .1..1..1
..0..0..0. .0..0..1. .0..0..0. .1..0..1. .0..0..0. .0..1..0. .1..1..1
..0..0..1. .0..1..1. .1..1..0. .1..0..0. .0..1..1. .0..0..1. .0..0..0
..0..0..1. .0..0..1. .0..0..0. .0..0..0. .0..1..1. .0..0..0. .0..0..0
..1..0..0. .1..1..0. .1..0..1. .1..1..0. .0..1..1. .1..0..0. .1..0..0
..0..1..0. .0..0..1. .1..0..1. .0..0..0. .0..0..0. .0..1..0. .1..0..0
CROSSREFS
Cf. A296952.
Sequence in context: A092466 A374296 A152618 * A255211 A172482 A362007
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 22 2017
STATUS
approved