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A281760
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Number of n X 3 0..1 arrays with no element unequal to a strict majority of its horizontal, diagonal and antidiagonal neighbors, with the exception of exactly one element, and with new values introduced in order 0 sequentially upwards.
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1
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2, 14, 47, 90, 201, 374, 672, 1172, 2015, 3442, 5859, 9952, 16876, 28574, 48309, 81554, 137477, 231418, 389016, 653080, 1095019, 1833842, 3067719, 5126372, 8557988, 14273314, 23784417, 39600082, 65880265, 109518782, 181933584, 302025692
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OFFSET
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1,1
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LINKS
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FORMULA
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Empirical: a(n) = 4*a(n-1) - 4*a(n-2) - 2*a(n-3) + 4*a(n-4) - a(n-6) for n>11.
Empirical g.f.: x*(2 + 6*x - x^2 - 38*x^3 + 49*x^4 - 32*x^5 - 26*x^6 + 36*x^7 + 6*x^8 + 8*x^9 + 8*x^10) / ((1 - x)^2*(1 - x - x^2)^2). - Colin Barker, Feb 20 2019
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EXAMPLE
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Some solutions for n=4:
..0..0..0. .0..0..0. .0..1..0. .0..0..0. .0..1..1. .0..0..0. .0..0..0
..0..0..0. .0..0..0. .0..0..0. .0..0..1. .1..1..1. .0..0..0. .1..0..0
..0..0..0. .0..0..0. .0..0..0. .0..0..0. .1..1..1. .0..1..0. .0..1..0
..1..1..0. .0..1..1. .0..0..0. .1..1..1. .1..1..1. .1..0..0. .1..0..1
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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