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A298722
Number of nX3 0..1 arrays with every element equal to 0, 2, 3, 5 or 8 king-move adjacent elements, with upper left element zero.
1
1, 7, 5, 15, 21, 57, 119, 285, 725, 1833, 4807, 12843, 34439, 93327, 254085, 693267, 1896489, 5194309, 14237415, 39049277, 107136761, 294009425, 806965323, 2215076227, 6080649203, 16692824711, 45826947389, 125811287255, 345400728813
OFFSET
1,2
COMMENTS
Column 3 of A298727.
LINKS
FORMULA
Empirical: a(n) = 5*a(n-1) -5*a(n-2) -5*a(n-3) -2*a(n-4) +18*a(n-5) +14*a(n-6) -30*a(n-7) -8*a(n-8) -22*a(n-9) +4*a(n-10) +84*a(n-11) +3*a(n-12) -33*a(n-13) -9*a(n-14) -21*a(n-15) +4*a(n-16) +4*a(n-17) for n>18
EXAMPLE
Some solutions for n=5
..0..1..1. .0..0..1. .0..1..0. .0..0..0. .0..0..0. .0..0..1. .0..1..1
..0..0..1. .1..0..0. .1..1..1. .0..0..0. .0..0..0. .1..0..0. .1..1..0
..1..0..1. .1..1..1. .0..0..0. .0..0..0. .0..0..0. .0..0..1. .0..0..0
..1..1..1. .1..0..1. .0..0..0. .1..1..1. .0..0..0. .1..0..0. .0..1..0
..0..1..0. .0..0..0. .0..0..0. .0..1..0. .0..0..0. .0..0..1. .1..1..1
CROSSREFS
Cf. A298727.
Sequence in context: A265794 A265818 A046557 * A299556 A282978 A125719
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 25 2018
STATUS
approved