A224004 Number of 6Xn 0..2 arrays with antidiagonals unimodal and rows and diagonals nondecreasing.

729, 20216, 117386, 388598, 984595, 2160036, 4368458, 8412641, 15703623, 28693082, 51589943, 91524689, 160402902, 277798382, 475383309, 803588211, 1341439640, 2210851797, 3597065144, 5777447600, 9161521721, 14345876103

Offset: 1

Author

R. H. Hardin Mar 30 2013

Keywords

• nonn

Comments

Row 6 of A223999

Examples

			Some solutions for n=3
..0..1..1....0..0..0....0..0..0....0..0..2....0..0..0....0..0..0....0..0..2
..0..1..2....0..0..2....0..2..2....1..1..2....0..2..2....0..0..0....0..1..1
..0..0..1....0..0..0....0..1..2....1..1..2....1..2..2....0..0..1....1..1..1
..0..2..2....0..0..0....1..1..1....0..1..1....0..1..2....1..1..2....0..2..2
..1..1..2....0..0..2....0..1..1....0..1..2....0..1..1....1..1..1....1..1..2
..1..1..2....1..1..2....2..2..2....1..2..2....0..2..2....0..1..2....0..1..2
		

Links

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

Formula

Empirical: a(n) = (1/3628800)*n^12 + (1/302400)*n^11 + (419/3628800)*n^10 + (223/120960)*n^9 + (35411/1209600)*n^8 + (20443/50400)*n^7 + (17616857/3628800)*n^6 + (6342323/120960)*n^5 + (821276033/1814400)*n^4 + (103253527/37800)*n^3 + (186412339/16800)*n^2 - (24901729/840)*n - 64275 for n>8