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A220046
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Number of 3Xn arrays of the minimum value of corresponding elements and their horizontal, diagonal 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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20, 59, 184, 848, 2902, 9055, 26963, 76874, 211179, 561525, 1448263, 3632759, 8883599, 21227329, 49658836, 113914079, 256565306, 567974512, 1237033071, 2652919602, 5606496287, 11683870637, 24026097363, 48778338927, 97822577971
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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) = (1/403291461126605635584000000)*n^26 - (1/2386340006666305536000000)*n^25 + (1/25852016738884976640000)*n^24 - (971/620448401733239439360000)*n^23 - (1291/29973352740736204800000)*n^22 + (264301/24523652242420531200000)*n^21 - (585619/817455074747351040000)*n^20 + (1702919/76636413257564160000)*n^19 + (55769939/430239513024921600000)*n^18 - (57873759473/1290718539074764800000)*n^17 + (9684348637/4639837885562880000)*n^16 - (3914078255459/83517081940131840000)*n^15 + (215018623323613/1206357850246348800000)*n^14 + (19576569823851979/835170819401318400000)*n^13 - (23533894850587963/27839027313377280000)*n^12 + (59609571604045123/3796230997278720000)*n^11 - (1007589571328254709/5975548792012800000)*n^10 + (51320300745894885721/80669908692172800000)*n^9 + (1920178014729925214233/153272826515128320000)*n^8 - (7985850767783833084087/25545471085854720000)*n^7 + (5195340624714198591739313/1170834091435008000000)*n^6 - (4720752658470992331022981/97569507619584000000)*n^5 + (594868732171829508743789/1496065783500288000)*n^4 - (278858662324669562498719/124672148625024000)*n^3 + (9915643693386144719/1312550965440)*n^2 - (35892062057123991/2974571600)*n + 3804040 for n>18
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EXAMPLE
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Some solutions for n=3
..1..0..0....2..0..2....2..0..0....0..0..0....0..0..0....1..1..1....2..1..1
..1..0..1....2..0..0....2..0..2....0..0..0....0..0..0....1..1..1....2..1..2
..1..3..1....3..0..1....2..1..1....3..3..3....1..1..3....3..3..3....3..2..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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