A225014 Number of 7Xn 0..1 arrays with rows unimodal and columns nondecreasing.

8, 64, 372, 1716, 6672, 22716, 69498, 194634, 505912, 1233584, 2845492, 6251596, 13154948, 26635774, 52097267, 98759971, 181971248, 326703424, 572756312, 982365976, 1651162688, 2723729944, 4415408372, 7042481236, 11063492816

Offset: 1

Author

R. H. Hardin Apr 23 2013

Keywords

• nonn

Comments

Row 7 of A225010

Examples

			Some solutions for n=3
..1..1..0....0..0..1....0..1..0....1..0..0....0..0..0....0..0..0....0..0..0
..1..1..0....0..0..1....1..1..0....1..0..0....0..1..0....0..0..0....0..1..0
..1..1..0....0..0..1....1..1..0....1..1..0....1..1..0....0..0..0....0..1..0
..1..1..0....0..0..1....1..1..0....1..1..0....1..1..0....0..0..1....1..1..0
..1..1..0....0..0..1....1..1..1....1..1..0....1..1..0....0..0..1....1..1..0
..1..1..0....0..1..1....1..1..1....1..1..1....1..1..1....0..1..1....1..1..0
..1..1..0....0..1..1....1..1..1....1..1..1....1..1..1....1..1..1....1..1..1
		

Links

• R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = (1/87178291200)*n^14 + (1/958003200)*n^13 + (43/958003200)*n^12 + (103/87091200)*n^11 + (1847/87091200)*n^10 + (7891/29030400)*n^9 + (1560493/609638400)*n^8 + (222427/12441600)*n^7 + (2023297/21772800)*n^6 + (1926401/5443200)*n^5 + (29332549/29937600)*n^4 + (1353853/739200)*n^3 + (183490757/75675600)*n^2 + (363/280)*n + 1