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A238810
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Number of nX6 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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7, 58, 498, 4167, 31125, 197418, 1055763, 4880856, 19977948, 73988808, 252222789, 801902972, 2401864834, 6830347670, 18555055873, 48388061335, 121621970223, 295617804194, 696809050142, 1596626133081, 3563675765061, 7762159805512
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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) = (1/1520925880320000)*n^21 - (521/4001483566080000)*n^20 + (280733/18246765061324800)*n^19 - (1009091/800296713216000)*n^18 + (1263428351/16005934264320000)*n^17 - (87961871/22417274880000)*n^16 + (157308110957/988601822208000)*n^15 - (561404357/105080976000)*n^14 + (32579981539913/217275125760000)*n^13 - (32002299106123/9053130240000)*n^12 + (507775457096141/7242504192000)*n^11 - (201470624506693/172440576000)*n^10 + (24782574974039318761/1520925880320000)*n^9 - (88935042592877896031/470762772480000)*n^8 + (127322197843062321569/70614415872000)*n^7 - (164460777264425293243/11769069312000)*n^6 + (1692671803663313850131/19615115520000)*n^5 - (3282324324299663003969/7939451520000)*n^4 + (598543228210824605143/405242838000)*n^3 - (57018800117252562839/15437822400)*n^2 + (25752092538637987/4476780)*n - 4188294729 for n>8
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EXAMPLE
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Some solutions for n=5
..0..0..0..0..2..2....0..0..0..0..2..2....0..2..2..0..0..0....0..0..0..2..2..0
..0..0..0..0..2..2....0..2..2..0..1..1....0..2..1..0..0..2....0..0..0..2..1..2
..0..0..2..2..0..1....0..2..1..0..0..0....0..0..0..0..2..2....0..0..0..0..2..2
..0..0..2..2..0..1....0..0..0..0..0..0....2..1..0..2..1..0....0..2..2..0..1..1
..2..2..1..1..0..2....2..1..0..0..0..0....2..1..0..2..2..1....2..1..2..1..2..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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