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A316736
Number of nX4 0..1 arrays with every element unequal to 1, 2, 3, 6, 7 or 8 king-move adjacent elements, with upper left element zero.
1
2, 33, 36, 95, 410, 392, 1124, 3964, 5343, 14856, 41918, 70345, 185864, 467659, 898506, 2269250, 5397846, 11232915, 27428849, 63595799, 138488643, 330375617, 758055990, 1692622361, 3976459935, 9093138520, 20578182687, 47876880000
OFFSET
1,1
COMMENTS
Column 4 of A316740.
LINKS
FORMULA
Empirical: a(n) = 3*a(n-1) +6*a(n-3) -31*a(n-4) +6*a(n-5) +10*a(n-6) +73*a(n-7) -15*a(n-8) -70*a(n-9) -42*a(n-10) -6*a(n-11) +63*a(n-12) +32*a(n-13) +12*a(n-14) -25*a(n-15) -20*a(n-16) -3*a(n-17) +4*a(n-18) +4*a(n-19) for n>24
EXAMPLE
Some solutions for n=5
..0..0..0..0. .0..0..1..1. .0..0..1..0. .0..0..1..1. .0..1..1..0
..0..1..1..0. .0..1..0..0. .1..0..1..1. .1..1..0..1. .0..0..1..0
..0..0..0..0. .0..0..0..0. .1..1..1..1. .1..1..1..1. .0..0..0..0
..0..0..1..0. .0..0..1..0. .1..1..0..1. .1..0..0..1. .0..1..1..0
..1..1..0..1. .0..1..1..0. .1..0..0..1. .0..1..1..0. .0..0..1..0
CROSSREFS
Cf. A316740.
Sequence in context: A078732 A305085 A042251 * A199551 A045932 A048783
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jul 11 2018
STATUS
approved