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A223807
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Number of nX3 0..3 arrays with rows, columns, diagonals and antidiagonals unimodal
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1
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50, 2500, 58806, 825896, 8165133, 62305953, 388531932, 2057610878, 9513089522, 39201336756, 146317003838, 501049337826, 1590725248238, 4722687426852, 13206968194237, 35002231000213, 88376951307032, 213545507535686
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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) = (89/169374965760)*n^18 + (838301/44460928512000)*n^17 + (131561/298896998400)*n^16 + (2899703/435891456000)*n^15 + (20728921/261534873600)*n^14 + (44295233/62270208000)*n^13 + (61053571/11496038400)*n^12 + (1555111843/50295168000)*n^11 + (157620907/1045094400)*n^10 + (3423292861/6096384000)*n^9 + (56948336183/32188907520)*n^8 + (18757539769/4790016000)*n^7 + (288950150603/37362124800)*n^6 + (2420059673699/326918592000)*n^5 + (12916777153/889574400)*n^4 + (2892057797/4540536000)*n^3 + (22972148831/1029188160)*n^2 - (1109957/29172)*n + 29
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EXAMPLE
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Some solutions for n=3
..2..2..1....0..3..3....0..3..3....1..2..0....0..0..0....0..0..1....2..0..0
..3..3..1....2..3..3....1..1..3....1..2..0....0..3..3....1..3..3....2..2..3
..0..2..1....3..3..0....0..1..2....3..2..0....1..3..3....1..2..2....2..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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