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A316513
Number of nX3 0..1 arrays with every element unequal to 0, 1, 2, 3, 7 or 8 king-move adjacent elements, with upper left element zero.
1
4, 21, 28, 75, 174, 414, 1002, 2398, 5743, 13785, 33053, 79248, 190054, 455751, 1092871, 2620730, 6284531, 15070301, 36138673, 86660727, 207812777, 498336020, 1195012127, 2865644552, 6871828916, 16478677644, 39515945239, 94759419700
OFFSET
1,1
COMMENTS
Column 3 of A316518.
LINKS
FORMULA
Empirical: a(n) = a(n-1) +2*a(n-2) +3*a(n-3) +a(n-4) -a(n-5) for n>8
EXAMPLE
Some solutions for n=5
..0..0..1. .0..1..0. .0..1..0. .0..0..1. .0..0..1. .0..0..0. .0..0..1
..0..1..0. .1..1..1. .1..1..1. .0..0..0. .0..0..0. .1..1..1. .0..1..0
..0..0..0. .1..0..1. .1..1..1. .0..1..0. .0..1..0. .1..1..1. .0..0..0
..0..0..0. .1..1..1. .1..1..1. .0..0..0. .1..0..0. .1..1..1. .0..1..0
..1..0..1. .0..1..1. .1..1..1. .1..0..1. .1..0..0. .0..0..0. .0..0..0
CROSSREFS
Cf. A316518.
Sequence in context: A356357 A276400 A304770 * A273208 A273270 A273246
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jul 05 2018
STATUS
approved