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A304539
Number of nX3 0..1 arrays with every element unequal to 0, 1, 3, 4 or 6 king-move adjacent elements, with upper left element zero.
1
3, 7, 9, 19, 37, 65, 129, 275, 555, 1143, 2417, 5101, 10937, 23873, 52511, 116647, 261813, 592025, 1347981, 3088537, 7111583, 16443119, 38153839, 88783305, 207079559, 483922933, 1132625887, 2654229335, 6226282429, 14617442181
OFFSET
1,1
COMMENTS
Column 3 of A304544.
LINKS
FORMULA
Empirical: a(n) = 3*a(n-1) -a(n-2) +2*a(n-3) -8*a(n-4) +2*a(n-5) -a(n-6) -a(n-7) -9*a(n-8) +3*a(n-9) +9*a(n-10) +8*a(n-11) +a(n-12) -3*a(n-13)
EXAMPLE
Some solutions for n=5
..0..0..0. .0..1..1. .0..0..1. .0..1..1. .0..1..1. .0..0..1. .0..0..0
..1..0..0. .1..1..1. .0..0..0. .1..1..1. .0..0..1. .0..1..1. .0..0..1
..1..1..0. .0..0..1. .0..0..0. .1..1..1. .1..1..1. .1..1..1. .0..1..1
..0..0..0. .0..1..1. .0..0..0. .1..1..1. .1..0..0. .1..1..1. .1..1..1
..1..0..0. .1..1..1. .0..0..1. .1..1..0. .1..1..0. .0..1..1. .1..1..1
CROSSREFS
Cf. A304544.
Sequence in context: A034926 A224849 A304128 * A306124 A096102 A316157
KEYWORD
nonn
AUTHOR
R. H. Hardin, May 14 2018
STATUS
approved