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A185471
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Number of (n+2)X5 0..2 arrays with each 3X3 subblock having rows and columns in lexicographically nondecreasing order
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1
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13659, 76309, 308692, 1043186, 3097348, 8297059, 20411234, 46732687, 100636591, 205574323, 401123377, 751921908, 1360579387, 2385984676, 4068843506, 6766785098, 11002001311, 17525142877, 27400120766, 42115574722, 63730107482
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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) = (1/444787200)*n^13
+ (107/479001600)*n^12
+ (11/1088640)*n^11
+ (3623/6220800)*n^10
+ (78227/3628800)*n^9
+ (6420917/14515200)*n^8
+ (148481/27216)*n^7
+ (1861160843/43545600)*n^6
+ (4966108109/21772800)*n^5
+ (1448539279/1555200)*n^4
+ (3663351401/1330560)*n^3
+ (2013261953/415800)*n^2
+ (15650889/3640)*n
+ 556
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EXAMPLE
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Some solutions for 4X5
..0..0..0..1..2....0..0..0..0..0....0..0..0..0..2....0..0..0..1..1
..0..0..1..1..2....0..0..1..2..2....0..0..0..2..2....0..0..0..1..2
..0..1..1..2..0....1..1..2..1..1....0..0..1..0..1....0..1..1..1..2
..2..1..2..0..2....2..2..2..1..2....1..2..2..1..1....1..1..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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