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A220012
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Number of 3Xn arrays of the minimum value of corresponding elements and their horizontal, vertical or antidiagonal neighbors in a random, but sorted with lexicographically nondecreasing rows and nonincreasing columns, 0..3 3Xn array
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1
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10, 20, 109, 479, 1735, 5686, 17525, 51891, 148887, 415328, 1127801, 2983759, 7698970, 19398768, 47793075, 115286948, 272626057, 632754218, 1442939429, 3236143029, 7144195995, 15536960940, 33309810566, 70444500191, 147041223854
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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) = (1/33607621760550469632000000)*n^26 - (29/5170403347776995328000000)*n^25 + (31/62044840173323943936000)*n^24 - (109/5442529839765258240000)*n^23 - (25027/67440043666656460800000)*n^22 + (46357/454141708192972800000)*n^21 - (483869/72128388948295680000)*n^20 + (24247537/102181884343418880000)*n^19 - (985474829/322679634768691200000)*n^18 - (34068475489/215119756512460800000)*n^17 + (479709089549/41758540970065920000)*n^16 - (138518494001/356910606581760000)*n^15 + (21512251671251281/2714305163054284800000)*n^14 - (10365455888214533/139195136566886400000)*n^13 - (47137945089864631/41758540970065920000)*n^12 + (38939213107138853/632705166213120000)*n^11 - (108277075670437250453/80669908692172800000)*n^10 + (82547306222649133721/4481661594009600000)*n^9 - (12081064949487162568993/76636413257564160000)*n^8 + (6497603208990962823589/12772735542927360000)*n^7 + (4044430533533808049709153/585417045717504000000)*n^6 - (39959078269525038081247/320952327696000000)*n^5 + (224843841913348330527047/220009674044160000)*n^4 - (2422774423532199558167/479508263942400)*n^3 + (14278279432468388566987/964724959598400)*n^2 - (36099811878753947/1673196525)*n + 7795656 for n>13
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EXAMPLE
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Some solutions for n=3
..3..0..0....2..0..0....1..0..0....1..1..1....2..2..2....3..1..1....2..2..2
..3..0..0....2..0..0....0..0..0....1..0..0....2..0..0....3..1..1....2..2..2
..3..3..3....3..1..1....0..0..0....0..0..0....0..0..0....3..2..2....2..2..2
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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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