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A303883
Number of nX3 0..1 arrays with every element unequal to 0, 2, 3 or 4 king-move adjacent elements, with upper left element zero.
2
1, 8, 11, 36, 87, 256, 684, 1932, 5308, 14809, 41025, 114088, 316733, 880136, 2444724, 6792145, 18868672, 52420409, 145629432, 404580097, 1123976982, 3122570154, 8674939898, 24100237936, 66953936965, 186007780911, 516756709968
OFFSET
1,2
COMMENTS
Column 3 of A303888.
LINKS
FORMULA
Empirical: a(n) = 3*a(n-1) +3*a(n-2) -10*a(n-3) +4*a(n-5) -16*a(n-6) +5*a(n-7) +17*a(n-8) -5*a(n-9) +3*a(n-10) +7*a(n-11) +7*a(n-12) +9*a(n-13) +3*a(n-14) +5*a(n-15) +2*a(n-16) for n>18
EXAMPLE
Some solutions for n=5
..0..1..0. .0..1..0. .0..0..1. .0..1..0. .0..0..1. .0..0..1. .0..1..1
..1..0..1. .1..1..0. .1..1..0. .0..1..0. .0..0..1. .1..1..0. .0..1..1
..1..0..0. .1..0..1. .1..1..1. .1..1..1. .1..1..0. .1..1..0. .0..1..1
..0..0..1. .0..0..0. .1..1..0. .0..1..0. .0..1..1. .0..0..1. .0..1..1
..1..1..0. .1..0..1. .1..1..0. .1..0..1. .0..1..0. .0..0..1. .1..0..0
CROSSREFS
Cf. A303888.
Sequence in context: A160796 A160416 A056873 * A304889 A192427 A258285
KEYWORD
nonn
AUTHOR
R. H. Hardin, May 02 2018
STATUS
approved