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A281060
Number of 5Xn 0..1 arrays with no element equal to more than one of its horizontal and antidiagonal neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards.
1
0, 122, 1492, 3416, 7803, 16875, 32370, 59669, 107693, 191953, 339219, 595824, 1041681, 1814253, 3149435, 5451162, 9409735, 16202663, 27835100, 47716151, 81633286, 139397983, 237621979, 404396106, 687167939, 1165993033, 1975805797
OFFSET
1,2
COMMENTS
Row 5 of A281056.
LINKS
FORMULA
Empirical: a(n) = 6*a(n-1) -12*a(n-2) +5*a(n-3) +12*a(n-4) -12*a(n-5) -3*a(n-6) +6*a(n-7) -a(n-9) for n>18
EXAMPLE
Some solutions for n=4
..0..1..0..1. .0..0..1..0. .0..1..1..0. .0..0..1..1. .0..1..0..1
..1..0..1..0. .0..0..1..0. .0..0..1..0. .1..0..0..1. .0..0..0..1
..1..1..0..1. .1..0..1..0. .1..1..1..1. .1..1..1..0. .1..1..0..1
..0..1..0..0. .1..0..1..0. .0..1..0..0. .1..0..1..0. .0..1..0..1
..0..1..1..0. .1..0..1..0. .0..1..1..0. .0..1..0..1. .0..0..1..0
CROSSREFS
Cf. A281056.
Sequence in context: A238033 A275181 A275129 * A274726 A249532 A222991
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 13 2017
STATUS
approved