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A238808
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Number of n X 4 0..2 arrays with no element equal to one plus the sum of elements to its left or one plus the sum of the sum of elements above it, modulo 3.
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1
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5, 25, 118, 468, 1501, 4167, 10423, 24115, 52449, 108395, 214496, 408732, 753333, 1347741, 2347301, 3989727, 6631953, 10800653, 17260510, 27105244, 41877485, 63724811, 95600675, 141520531, 206885249, 298885895, 427006156, 603641124
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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) = (1/302400)*n^10 - (13/90720)*n^9 + (37/6720)*n^8 - (451/3780)*n^7 + (29063/14400)*n^6 - (100891/4320)*n^5 + (11871787/60480)*n^4 - (25402589/22680)*n^3 + (35075741/8400)*n^2 - (2861612/315)*n + 8719 for n>4.
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EXAMPLE
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Some solutions for n=5
..2..2..0..0....0..0..0..0....0..0..2..2....0..0..0..2....0..0..0..0
..2..1..0..0....0..2..2..0....2..2..1..1....2..2..0..1....0..2..2..0
..0..0..0..2....0..2..1..0....2..1..2..2....2..1..0..0....0..2..2..0
..0..0..2..1....0..0..2..2....0..2..2..1....0..2..2..0....2..1..0..2
..0..2..1..0....2..1..2..2....0..2..1..0....0..2..1..2....2..2..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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