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A299329
Number of nX3 0..1 arrays with every element equal to 2, 3, 4, 5, 6 or 7 king-move adjacent elements, with upper left element zero.
1
0, 3, 8, 36, 173, 858, 4258, 21386, 107465, 541047, 2725498, 13733762, 69215100, 348852964, 1758324488, 8862635135, 44671460074, 225164071583, 1134929377517, 5720565544510, 28834291127949, 145338167739511, 732571679461791
OFFSET
1,2
COMMENTS
Column 3 of A299334.
LINKS
FORMULA
Empirical: a(n) = 4*a(n-1) +10*a(n-2) -13*a(n-3) -53*a(n-4) -25*a(n-5) +57*a(n-6) +53*a(n-7) +a(n-8) +16*a(n-9) +10*a(n-10) -15*a(n-11) -4*a(n-12) for n>14
EXAMPLE
Some solutions for n=5
..0..1..1. .0..1..1. .0..0..0. .0..0..1. .0..0..0. .0..0..0. .0..1..1
..0..0..1. .0..0..1. .0..0..1. .0..1..1. .0..0..0. .0..1..0. .0..0..1
..0..1..1. .0..0..0. .0..1..1. .1..1..1. .0..1..0. .1..0..1. .1..1..0
..0..1..1. .0..1..0. .0..1..0. .1..0..0. .0..1..1. .1..1..0. .0..1..0
..0..0..1. .1..1..1. .0..0..0. .0..0..0. .0..0..1. .1..0..0. .0..0..0
CROSSREFS
Cf. A299334.
Sequence in context: A148919 A087905 A295103 * A362362 A020111 A367640
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 07 2018
STATUS
approved