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A224357
Number of 6Xn 0..2 arrays with diagonals and antidiagonals unimodal and rows nondecreasing
1
729, 46656, 349280, 1351748, 4231138, 12340932, 34697869, 94262290, 246254814, 616242552, 1475123504, 3379586703, 7423803582, 15672970622, 31884279651, 62668814332, 119312143790, 220555944774, 396752366132, 695942226325
OFFSET
1,1
COMMENTS
Row 6 of A224353
LINKS
FORMULA
Empirical: a(n) = (761/8553600)*n^12 + (1733/3326400)*n^11 + (1459/108864)*n^10 + (4187/40320)*n^9 + (1551227/1814400)*n^8 + (72841/12600)*n^7 + (1802801/19440)*n^6 - (66259339/120960)*n^5 + (9020552353/1360800)*n^4 - (817656577/50400)*n^3 + (5508355001/83160)*n^2 - (57456263/1540)*n - 269256 for n>7
EXAMPLE
Some solutions for n=3
..0..0..0....0..0..0....0..0..0....0..0..0....0..0..2....0..0..2....0..0..1
..2..2..2....1..2..2....0..1..2....0..0..0....0..0..2....1..1..1....0..1..2
..0..1..2....0..1..1....1..1..2....0..0..1....0..2..2....0..1..1....0..2..2
..0..0..1....1..2..2....0..1..1....0..2..2....0..0..2....1..1..1....1..2..2
..0..0..1....2..2..2....1..1..1....0..2..2....0..1..2....1..1..2....0..2..2
..0..0..1....1..2..2....0..2..2....2..2..2....0..0..0....0..1..2....1..1..1
CROSSREFS
Sequence in context: A036536 A223281 A268976 * A016770 A224016 A059978
KEYWORD
nonn
AUTHOR
R. H. Hardin Apr 04 2013
STATUS
approved