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A220156
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Number of 4Xn arrays of the minimum value of corresponding elements and their horizontal or diagonal neighbors in a random, but sorted with lexicographically nondecreasing rows and nonincreasing columns, 0..2 4Xn array
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1
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15, 52, 242, 1174, 4559, 16110, 53947, 173732, 539903, 1620236, 4698464, 13180052, 35802185, 94277039, 240952485, 598495844, 1446788180, 3408685943, 7838407335, 17616947657, 38749982170, 83520468048, 176604065342, 366743870453
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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) = (1/969450627708186624000000)*n^25 - (1/4562120600979701760000)*n^24 + (2027/77556050216654929920000)*n^23 - (331/177473799122780160000)*n^22 + (5539/80669908692172800000)*n^21 + (5921/3128016867655680000)*n^20 - (18577907/38318206628782080000)*n^19 + (18754471/474528874659840000)*n^18 - (41570691557/20167477173043200000)*n^17 + (5382522617/73004442255360000)*n^16 - (17042278220257/10439635242516480000)*n^15 + (9851672121271/1491376463216640000)*n^14 + (58162480943607049/52198176212582400000)*n^13 - (135094442095532831/2609908810629120000)*n^12 + (635574550376155319/474528874659840000)*n^11 - (1347751237421517133/59316109332480000)*n^10 + (296554709147396003149/1260467323315200000)*n^9 - (2610520959289132961/4236864952320000)*n^8 - (80984035976231237377421/3193183885731840000)*n^7 + (22349422485612993076363/44349776190720000)*n^6 - (7737663764129137016063569/1524523556556000000)*n^5 + (3378006014145622282711/109727291520000)*n^4 - (83444980373091022514603/820211504112000)*n^3 + (294465474881972180993/4365271310400)*n^2 + (987245448964903837/1487285800)*n - 1630947583 for n>18
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EXAMPLE
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Some solutions for n=3
..0..0..0....1..0..0....1..0..0....0..0..0....0..0..0....1..0..0....1..1..1
..1..0..0....1..0..0....1..0..0....1..0..0....0..0..0....2..0..0....1..0..1
..1..1..1....2..0..0....2..0..0....1..1..2....1..1..0....2..1..1....1..0..0
..2..2..1....2..0..0....2..1..1....1..1..1....1..1..1....2..2..2....1..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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