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A283721
Number of nX3 0..1 arrays with no 1 equal to more than two of its horizontal, diagonal and antidiagonal neighbors, with the exception of exactly one element.
1
0, 10, 159, 1304, 9819, 69972, 478164, 3182364, 20764075, 133429620, 847160264, 5326384974, 33218865533, 205768886352, 1267218413380, 7765068162382, 47373987672324, 287914794741192, 1743841385348260, 10529990498553708
OFFSET
1,2
COMMENTS
Column 3 of A283726.
LINKS
FORMULA
Empirical: a(n) = 10*a(n-1) -21*a(n-2) +8*a(n-3) -162*a(n-4) +38*a(n-5) -270*a(n-6) +654*a(n-7) +231*a(n-8) +1484*a(n-9) -390*a(n-10) -508*a(n-11) -2885*a(n-12) -2464*a(n-13) -316*a(n-14) +1760*a(n-15) +4524*a(n-16) +1888*a(n-17) -96*a(n-18) -1920*a(n-19) -1600*a(n-20)
EXAMPLE
Some solutions for n=4
..1..0..0. .1..1..1. .1..0..1. .1..0..1. .0..1..1. .1..0..1. .1..1..0
..0..1..1. .0..1..0. .0..1..0. .1..1..1. .0..1..0. .0..1..1. .0..1..0
..1..0..0. .1..0..1. .1..0..0. .1..0..1. .1..0..0. .0..0..0. .1..0..1
..0..1..1. .0..0..1. .0..1..0. .0..1..0. .1..1..1. .0..1..0. .1..0..0
CROSSREFS
Cf. A283726.
Sequence in context: A129460 A200989 A268883 * A239761 A245916 A245914
KEYWORD
nonn
AUTHOR
R. H. Hardin, Mar 15 2017
STATUS
approved