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A223863
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Number of nX7 0..3 arrays with rows and antidiagonals unimodal and columns nondecreasing
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1
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1163, 165212, 6818350, 144081276, 2030417942, 21476594002, 181330154458, 1271807435844, 7630189031428, 40055722078772, 187351337881293, 792277748611083, 3065939800657297, 10966696897925829, 36566451416331144
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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) = (3642102403/12772735542927360000)*n^21 + (3642102403/304112751022080000)*n^20 + (5501403851/18246765061324800)*n^19 + (1301866883/246245142528000)*n^18 + (321344829121/4573124075520000)*n^17 + (9671690543/13076743680000)*n^16 + (48483224873/7604629401600)*n^15 + (4261834903427/94152554496000)*n^14 + (1535291055316393/5649153269760000)*n^13 + (98414490687917/72425041920000)*n^12 + (170390859823/29561241600)*n^11 + (33527325663863/1609445376000)*n^10 + (2567156664752496221/39544072888320000)*n^9 + (78187026472193263/470762772480000)*n^8 + (8882688677555591/28245766348800)*n^7 + (112344931028903/452656512000)*n^6 - (18857407511117083/95273418240000)*n^5 - (193916745450429061/55576160640000)*n^4 - (232978788696097/75811583232)*n^3 + (3865849954293617/293318625600)*n^2 + (834897119951/9699690)*n - 164695 for n>6
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EXAMPLE
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Some solutions for n=3
..0..0..0..0..0..0..0....0..0..0..2..2..2..0....0..0..0..0..1..1..1
..0..0..0..0..0..0..1....0..0..0..2..3..3..2....0..0..0..2..2..1..1
..0..0..0..0..0..2..1....0..0..1..2..3..3..3....0..0..3..3..3..3..3
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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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