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A317761
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Number of n X 5 0..1 arrays with every element unequal to 0, 1 or 2 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.
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1
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16, 42, 52, 72, 109, 177, 302, 532, 955, 1733, 3164, 5796, 10637, 19541, 35918, 66040, 121443, 223345, 410772, 755504, 1389565, 2555785, 4700798, 8646092, 15902619, 29249453, 53798108, 98950124, 181997629, 334745805, 615693502, 1132436880
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OFFSET
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1,1
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COMMENTS
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LINKS
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FORMULA
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Empirical: a(n) = 2*a(n-1) - a(n-4) for n > 6.
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EXAMPLE
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Some solutions for n=5:
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 0 0
1 1 1 1 1 1 1 1 1 1 0 0 0 0 1 1 1 0 0 0
1 1 1 1 1 1 1 1 1 1 0 0 0 1 1 1 0 0 0 0
1 1 1 1 1 1 1 1 1 0 0 0 1 1 1 0 0 0 0 0
0 0 0 0 0 1 1 1 0 0 0 1 1 1 1 0 0 0 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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