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A298836
Number of n X 3 0..1 arrays with every element equal to 2, 3, 4, 5 or 8 king-move adjacent elements, with upper left element zero.
1
0, 3, 9, 21, 127, 513, 2440, 11458, 53727, 254534, 1202650, 5692243, 26943691, 127540324, 603796896, 2858444154, 13532486972, 64065914939, 303303284790, 1435912281177, 6797962755503, 32183241315912, 152363457753491
OFFSET
1,2
COMMENTS
Column 3 of A298841.
LINKS
FORMULA
Empirical: a(n) = 5*a(n-1) +6*a(n-2) -31*a(n-3) -40*a(n-4) +100*a(n-5) +105*a(n-6) -167*a(n-7) -101*a(n-8) +118*a(n-9) +29*a(n-10) -19*a(n-11) +4*a(n-12) for n>14.
EXAMPLE
Some solutions for n=7
..0..0..0. .0..0..0. .0..1..1. .0..0..0. .0..0..0. .0..0..0. .0..0..0
..0..0..0. .0..0..0. .0..0..1. .0..0..0. .0..0..0. .0..1..0. .0..0..0
..0..0..0. .0..0..0. .1..0..1. .0..0..0. .1..1..1. .1..1..1. .0..0..0
..1..1..1. .0..0..0. .1..1..1. .1..1..1. .1..1..1. .0..0..0. .1..1..1
..1..0..1. .0..0..0. .0..0..0. .1..1..0. .1..1..1. .0..0..0. .0..1..1
..0..1..0. .1..1..1. .0..0..0. .1..0..0. .1..1..1. .0..0..0. .0..0..1
..0..0..0. .1..1..1. .0..0..0. .1..1..0. .1..1..1. .0..0..0. .0..0..0
CROSSREFS
Cf. A298841.
Sequence in context: A074000 A067645 A101474 * A252284 A259367 A193374
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 27 2018
STATUS
approved