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A251384
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Number of (n+1) X (2+1) 0..2 arrays with every 2 X 2 subblock summing to 2 3 4 5 or 6.
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1
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571, 12457, 271393, 5914339, 128887759, 2808783981, 61210372853, 1333925956743, 29069557621363, 633497816232785, 13805489867099657, 300855891824364491, 6556396659359553239, 142880157321162697173, 3113713281361245496797
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OFFSET
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1,1
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LINKS
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R. H. Hardin, Table of n, a(n) for n = 1..210
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FORMULA
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Empirical: a(n) = 23*a(n-1) - 21*a(n-2) - 119*a(n-3) + 66*a(n-4) + 72*a(n-5) - 32*a(n-6).
Empirical g.f.: x*(571 - 676*x - 3127*x^2 + 1846*x^3 + 1912*x^4 - 864*x^5) / (1 - 23*x + 21*x^2 + 119*x^3 - 66*x^4 - 72*x^5 + 32*x^6). - Colin Barker, Nov 29 2018
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EXAMPLE
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Some solutions for n=2:
..1..2..1....2..0..2....1..2..2....0..2..1....1..2..1....2..2..2....1..0..1
..0..2..0....2..2..0....2..0..0....0..1..0....0..1..2....1..0..2....1..2..1
..2..0..0....1..1..2....0..1..1....1..1..2....1..1..2....1..2..1....2..1..0
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CROSSREFS
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Column 2 of A251390.
Sequence in context: A073036 A020381 A142767 * A076465 A144956 A178323
Adjacent sequences: A251381 A251382 A251383 * A251385 A251386 A251387
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KEYWORD
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nonn
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AUTHOR
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R. H. Hardin, Dec 01 2014
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STATUS
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approved
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