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A317113
Number of nX3 0..1 arrays with every element unequal to 0, 1, 2, 3, 4, 7 or 8 king-move adjacent elements, with upper left element zero.
1
4, 30, 142, 698, 3398, 16686, 81809, 401415, 1969107, 9660093, 47389711, 232481946, 1140496397, 5594981980, 27447541559, 134650576212, 660561074466, 3240542648641, 15897268312271, 77987907394984, 382588604448738
OFFSET
1,1
COMMENTS
Column 3 of A317118.
LINKS
FORMULA
Empirical: a(n) = 3*a(n-1) +10*a(n-2) -a(n-3) -12*a(n-4) +7*a(n-5) -a(n-6) -20*a(n-7) +15*a(n-8) -3*a(n-9) -3*a(n-10) for n>12
EXAMPLE
Some solutions for n=5
..0..1..0. .0..0..0. .0..0..1. .0..0..1. .0..0..0. .0..0..1. .0..0..0
..1..1..1. .1..1..1. .0..1..0. .1..0..0. .0..0..0. .0..1..0. .1..0..0
..1..1..1. .0..1..1. .1..1..1. .0..1..0. .0..1..0. .0..0..0. .1..1..0
..0..0..1. .1..0..1. .0..1..1. .0..0..0. .0..1..0. .1..0..0. .1..1..1
..0..0..0. .0..0..0. .0..1..1. .1..0..0. .0..0..0. .1..1..1. .1..1..1
CROSSREFS
Cf. A317118.
Sequence in context: A316178 A375260 A305764 * A123351 A305525 A316999
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jul 21 2018
STATUS
approved