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A283687
Number of nX4 0..1 arrays with no 1 equal to more than two of its horizontal, diagonal and antidiagonal neighbors.
1
16, 161, 1521, 15226, 150497, 1489917, 14754038, 146079023, 1446386879, 14321176544, 141798827829, 1403999090083, 13901477028478, 137643299572877, 1362853595880357, 13494081631456544, 133609537897145821
OFFSET
1,1
COMMENTS
Column 4 of A283691.
LINKS
FORMULA
Empirical: a(n) = 7*a(n-1) +24*a(n-2) +55*a(n-3) -57*a(n-4) -195*a(n-5) -458*a(n-6) +154*a(n-7) +630*a(n-8) +634*a(n-9) -160*a(n-10) -239*a(n-11) -42*a(n-12) -20*a(n-13) -8*a(n-14)
EXAMPLE
Some solutions for n=4
..1..0..0..1. .0..0..0..0. .0..1..0..1. .0..1..0..0. .0..0..0..1
..0..1..0..0. .0..1..0..0. .0..1..0..0. .1..1..0..1. .0..0..1..1
..0..0..0..1. .0..0..0..0. .1..0..0..0. .0..0..0..0. .1..0..1..0
..1..1..1..0. .0..0..0..0. .1..0..0..1. .0..1..1..0. .0..0..1..1
CROSSREFS
Cf. A283691.
Sequence in context: A204297 A000811 A041484 * A011551 A335175 A238533
KEYWORD
nonn
AUTHOR
R. H. Hardin, Mar 14 2017
STATUS
approved