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A298890
Number of nX3 0..1 arrays with every element equal to 2, 3, 5, 6 or 8 king-move adjacent elements, with upper left element zero.
1
0, 3, 1, 4, 4, 11, 26, 66, 171, 462, 1248, 3419, 9450, 26334, 73697, 206960, 582316, 1640549, 4625476, 13047636, 36816651, 103906694, 293290860, 827923703, 2337253142, 6598367806, 18628473233, 52592572696, 148482655256, 419208157101
OFFSET
1,2
COMMENTS
Column 3 of A298895.
LINKS
FORMULA
Empirical: a(n) = 4*a(n-1) -a(n-2) -5*a(n-3) -10*a(n-4) +11*a(n-5) +15*a(n-6) +2*a(n-7) -5*a(n-8) -33*a(n-9) -20*a(n-10) +47*a(n-11) +36*a(n-12) +4*a(n-14) -12*a(n-15) -2*a(n-16) +2*a(n-17) for n>18
EXAMPLE
Some solutions for n=7
..0..0..0. .0..0..1. .0..0..0. .0..0..0. .0..1..1. .0..0..0. .0..1..1
..0..0..0. .0..1..1. .0..0..0. .0..0..0. .0..0..1. .1..0..1. .0..0..1
..1..1..1. .1..0..0. .0..0..0. .1..1..1. .1..0..1. .1..1..1. .1..0..1
..0..1..0. .1..0..1. .0..0..0. .1..1..1. .1..1..0. .0..0..1. .1..1..0
..0..0..0. .1..1..1. .1..1..1. .0..0..0. .1..0..1. .0..1..0. .0..0..0
..0..1..0. .1..0..1. .1..1..1. .0..0..0. .0..0..1. .1..1..0. .0..1..0
..1..1..1. .0..0..0. .1..1..1. .0..0..0. .0..1..1. .1..0..0. .1..1..1
CROSSREFS
Cf. A298895.
Sequence in context: A363569 A200027 A370807 * A016473 A343516 A366977
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 28 2018
STATUS
approved