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A224163
Number of 7Xn 0..1 arrays with diagonals and rows unimodal and antidiagonals nondecreasing
1
128, 2916, 9681, 18408, 32910, 60214, 114537, 222841, 437497, 857104, 1662992, 3177801, 5958392, 10937977, 19639113, 34486391, 59258268, 99731248, 164588012, 266685480, 424810970, 666096886, 1029319580, 1569379741, 2363354232
OFFSET
1,1
COMMENTS
Row 7 of A224158
LINKS
FORMULA
Empirical: a(n) = (1/87178291200)*n^14 - (1/1779148800)*n^13 + (1/35481600)*n^12 - (599/958003200)*n^11 + (2503/87091200)*n^10 - (15289/29030400)*n^9 + (14386957/609638400)*n^8 - (43214887/87091200)*n^7 + (53001143/7257600)*n^6 - (371883179/5443200)*n^5 + (31780522507/59875200)*n^4 - (22988847851/6652800)*n^3 + (639379939651/30270240)*n^2 - (888679471/10010)*n + 189847 for n>10
EXAMPLE
Some solutions for n=3
..0..0..0....1..0..0....0..1..0....0..0..0....0..0..1....0..0..0....1..1..0
..0..0..0....1..0..0....1..0..0....0..1..0....1..1..1....0..0..1....1..0..0
..0..0..0....0..0..0....0..0..0....1..0..0....1..1..1....1..1..0....1..1..0
..1..0..0....0..0..0....1..0..0....1..0..0....1..1..0....1..0..0....1..0..0
..0..0..0....0..0..1....1..0..0....0..0..0....1..0..0....0..1..0....0..1..0
..1..0..0....1..1..0....1..0..0....1..0..0....1..0..0....1..1..0....1..0..0
..0..0..0....1..1..1....1..1..0....0..0..0....1..1..0....1..0..0....1..0..0
CROSSREFS
Sequence in context: A221662 A250282 A019564 * A224414 A128802 A297613
KEYWORD
nonn
AUTHOR
R. H. Hardin Mar 31 2013
STATUS
approved