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A300771
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Number of nX3 0..1 arrays with every element equal to 2, 3, 4 or 6 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.
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1
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0, 2, 3, 11, 32, 102, 330, 1059, 3418, 11023, 35561, 114744, 370251, 1194696, 3854994, 12439181, 40138345, 129517277, 417922738, 1348541219, 4351434893, 14041088118, 45307389076, 146196612400, 471743129235, 1522207498886, 4911816468097
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OFFSET
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1,2
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COMMENTS
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LINKS
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FORMULA
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Empirical: a(n) = 3*a(n-1) +3*a(n-3) -3*a(n-4) +5*a(n-5) -2*a(n-6) -11*a(n-7) -13*a(n-8) +11*a(n-9) -2*a(n-10) -5*a(n-11) +a(n-12) +5*a(n-13) -4*a(n-14) +a(n-15)
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EXAMPLE
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Some solutions for n=5
..0..0..1. .0..0..0. .0..0..1. .0..0..1. .0..0..1. .0..0..1. .0..0..1
..0..1..1. .0..0..1. .0..1..1. .0..1..1. .0..1..1. .0..1..1. .0..1..1
..1..1..1. .0..1..1. .0..0..0. .0..0..0. .0..1..1. .1..1..1. .0..1..1
..0..0..1. .0..1..0. .1..1..0. .0..0..1. .0..1..0. .1..1..0. .0..0..1
..0..1..1. .0..0..0. .1..0..0. .0..1..1. .0..0..0. .1..0..0. .0..1..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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