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A280156
Number of nX3 0..1 arrays with no element unequal to a strict majority of its horizontal, vertical and antidiagonal neighbors, with the exception of exactly one element, and with new values introduced in order 0 sequentially upwards.
1
2, 8, 31, 94, 305, 950, 2901, 8728, 26068, 77326, 228367, 671446, 1967328, 5745190, 16730555, 48594066, 140815777, 407186706, 1175159395, 3385527188, 9737463217, 27964574958, 80197812317, 229694924100, 657073271390, 1877519404364
OFFSET
1,1
COMMENTS
Column 3 of A280161.
LINKS
FORMULA
Empirical: a(n) = 6*a(n-1) -7*a(n-2) -18*a(n-3) +45*a(n-4) -22*a(n-5) -38*a(n-6) +74*a(n-7) -39*a(n-8) -2*a(n-9) +4*a(n-10) +2*a(n-11) -8*a(n-12) -4*a(n-13) -a(n-14) for n>19
EXAMPLE
Some solutions for n=4
..0..0..0. .0..0..0. .0..1..1. .0..1..1. .0..1..1. .0..0..0. .0..0..1
..0..0..0. .1..1..0. .0..1..1. .0..0..1. .0..1..1. .0..0..0. .0..0..0
..0..0..1. .1..1..1. .0..1..1. .0..0..1. .0..0..0. .0..0..0. .1..1..0
..0..0..0. .1..1..1. .0..0..1. .0..1..1. .1..0..0. .0..0..1. .1..1..0
CROSSREFS
Cf. A280161.
Sequence in context: A294264 A367037 A007468 * A054137 A343414 A062456
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 27 2016
STATUS
approved