A224314 Number of 6Xn 0..2 arrays with diagonals and rows unimodal and antidiagonals nondecreasing.

729, 69984, 615481, 2717759, 9829605, 33934344, 118317987, 416543502, 1454734611, 4952178320, 16233385381, 50895787205, 152210262323, 434202798968, 1183383351150, 3089018682146, 7745205810204, 18709904381707, 43674432900423

Offset: 1

Author

R. H. Hardin Apr 03 2013

Keywords

• nonn

Comments

Row 6 of A224310

Examples

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

Links

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

Formula

Empirical: a(n) = (1/35608838483312640000)*n^24 - (1/989134402314240000)*n^23 + (29/340606281144729600)*n^22 - (53/37347179950080000)*n^21 + (22843/270322445352960000)*n^20 - (9467/35777970708480000)*n^19 + (662659/9959247986688000)*n^18 + (276971/2196892938240000)*n^17 + (3268463573/52725430517760000)*n^16 - (2963663/488198430720000)*n^15 + (9468406841/251073478656000)*n^14 - (84633169147/72425041920000)*n^13 + (487482300065231/17575143505920000)*n^12 - (1486260397277527/4393785876480000)*n^11 + (9918644607332189/5272543051776000)*n^10 + (43388314670213341/2196892938240000)*n^9 - (3089001310329622433/5335311421440000)*n^8 + (16161770203432180709/2000741783040000)*n^7 - (9131503366840338348499/106439462857728000)*n^6 + (11613280481413038257281/14783258730240000)*n^5 - (88365905776581806936999/14783258730240000)*n^4 + (4417617587739169133/127135008000)*n^3 - (377212760667401564861/2698531355520)*n^2 + (557689056867461/1615152)*n - 399418303 for n>12