A224016 Number of 6Xn 0..2 arrays with rows nondecreasing and antidiagonals unimodal.

729, 46656, 534352, 3094127, 13275381, 47735665, 150787422, 430109607, 1128769430, 2762176256, 6366017979, 13926332849, 29098170483, 58367669325, 112877225362, 211218704199, 383609908528, 678009948228, 1168905645807

Offset: 1

Author

R. H. Hardin Mar 30 2013

Keywords

• nonn

Comments

Row 6 of A224012

Examples

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

Links

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

Formula

Empirical: a(n) = (761/8553600)*n^12 + (811/302400)*n^11 + (4879/97200)*n^10 + (230029/362880)*n^9 + (10666727/1814400)*n^8 + (6162019/151200)*n^7 + (76144063/388800)*n^6 + (1772311/2688)*n^5 + (230134279/194400)*n^4 + (14927389/453600)*n^3 - (7982908/51975)*n^2 + (2910398/315)*n + 7207 for n>4