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A304014
Number of nX3 0..1 arrays with every element unequal to 1, 2, 3 or 5 king-move adjacent elements, with upper left element zero.
1
1, 16, 38, 103, 281, 826, 2421, 7104, 20732, 61087, 179751, 529548, 1561475, 4603482, 13574654, 40041939, 118101915, 348367166, 1027637463, 3031343374, 8942116280, 26378505409, 77814052747, 229545502386, 677142752205, 1997520929872
OFFSET
1,2
COMMENTS
Column 3 of A304019.
LINKS
FORMULA
Empirical: a(n) = 2*a(n-1) +4*a(n-2) +3*a(n-3) -13*a(n-4) -20*a(n-5) +6*a(n-6) -21*a(n-7) +23*a(n-8) +63*a(n-9) +36*a(n-10) +14*a(n-11) -55*a(n-12) -43*a(n-13) -7*a(n-14) +26*a(n-15) +25*a(n-16) -6*a(n-17) +4*a(n-18) -4*a(n-20)
EXAMPLE
Some solutions for n=5
..0..1..0. .0..0..1. .0..0..0. .0..0..1. .0..0..1. .0..0..1. .0..1..1
..1..1..0. .0..1..0. .0..1..1. .0..1..1. .0..1..1. .0..1..1. .1..1..0
..0..0..1. .1..1..0. .1..1..0. .0..1..0. .1..1..1. .0..0..1. .0..0..0
..0..1..1. .0..0..1. .1..1..1. .1..0..0. .1..1..0. .1..1..0. .0..0..0
..0..0..1. .1..0..1. .1..0..1. .1..1..1. .0..1..1. .0..1..0. .1..1..1
CROSSREFS
Cf. A304019.
Sequence in context: A070586 A166112 A224738 * A230828 A122030 A122029
KEYWORD
nonn
AUTHOR
R. H. Hardin, May 04 2018
STATUS
approved