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A281053
Number of nX5 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
2, 104, 618, 2452, 7803, 22106, 58005, 144283, 344972, 800225, 1812024, 4023754, 8791481, 18948288, 40366695, 85135873, 177990242, 369259703, 760850914, 1558181104, 3173635543, 6432024694, 12977428633, 26076680087, 52202242904
OFFSET
1,1
COMMENTS
Column 5 of A281056.
LINKS
FORMULA
Empirical: a(n) = 5*a(n-1) -6*a(n-2) -4*a(n-3) +5*a(n-4) +9*a(n-5) -12*a(n-7) -3*a(n-8) +3*a(n-9) +6*a(n-10) -a(n-12) -a(n-13) for n>16
EXAMPLE
Some solutions for n=4
..0..1..1..0..1. .0..0..1..0..1. .0..0..0..1..0. .0..1..0..1..0
..1..0..1..0..1. .1..1..1..0..0. .1..1..0..1..1. .0..1..1..0..1
..1..0..1..0..1. .1..0..1..1..0. .0..1..0..0..0. .1..0..1..0..0
..0..0..1..0..0. .0..1..0..1..0. .0..1..0..1..0. .1..0..1..1..0
CROSSREFS
Cf. A281056.
Sequence in context: A106299 A176933 A246775 * A101530 A199945 A346165
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 13 2017
STATUS
approved