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A304136
Number of n X 3 0..1 arrays with every element unequal to 0, 2, 3 or 6 king-move adjacent elements, with upper left element zero.
1
1, 7, 5, 9, 15, 16, 33, 57, 62, 133, 231, 256, 549, 953, 1074, 2281, 3951, 4524, 9497, 16409, 19078, 39581, 68215, 80488, 165085, 283801, 339658, 688993, 1181567, 1433652, 2877361, 4922681, 6052414, 12023669, 20522759, 25555920, 50272981
OFFSET
1,2
COMMENTS
Column 3 of A304141.
LINKS
FORMULA
Empirical: a(n) = a(n-1) +a(n-2) +5*a(n-3) -5*a(n-4) -5*a(n-5) -4*a(n-6) +4*a(n-7) +4*a(n-8) for n>10.
EXAMPLE
Some solutions for n=5
..0..1..0. .0..0..0. .0..0..1. .0..1..0. .0..0..0. .0..1..0. .0..0..0
..1..1..0. .1..1..1. .0..0..1. .1..0..1. .0..0..0. .1..0..1. .0..0..0
..0..0..0. .1..1..1. .0..0..1. .1..1..1. .0..0..0. .1..1..1. .0..0..0
..0..1..0. .1..1..1. .0..0..1. .1..0..1. .1..1..1. .0..0..1. .0..0..0
..1..0..1. .1..1..1. .0..0..1. .0..1..0. .1..1..1. .1..0..1. .0..0..0
CROSSREFS
Cf. A304141.
Sequence in context: A351212 A323669 A356526 * A305042 A247870 A367689
KEYWORD
nonn
AUTHOR
R. H. Hardin, May 07 2018
STATUS
approved