A224192 Number of 5Xn 0..2 arrays with rows unimodal and columns nondecreasing

21, 441, 5852, 55438, 408222, 2469182, 12741432, 57644194, 233385140, 859145920, 2912085006, 9181289736, 27151590510, 75840301088, 201262238349, 509972027785, 1239109721281, 2897739996141, 6543276177902, 14306873805792, 30366198279340

Offset

1,1

Comments

Row 5 of A224190

Links

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

Formula

Empirical: a(n) = (1/1379196149760000)*n^20 + (1/12538146816000)*n^19 + (467/101624979456000)*n^18 + (223/1302884352000)*n^17 + (9641/2134978560000)*n^16 + (44237/498161664000)*n^15 + (115879/86102016000)*n^14 + (24029081/1494484992000)*n^13 + (623419/4055040000)*n^12 + (18199033/15328051200)*n^11 + (3421967251/459841536000)*n^10 + (263944057/6967296000)*n^9 + (8168948285977/52306974720000)*n^8 + (193145489021/373621248000)*n^7 + (507138710909/373621248000)*n^6 + (13262560631/4790016000)*n^5 + (3783062210933/882161280000)*n^4 + (108121887773/22054032000)*n^3 + (27314271011/6518191680)*n^2 + (14737223/8314020)*n + 1

Example

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

Crossrefs

Sequence in context: A188770 A223922 A224350 * A207184 A189060 A224009

Adjacent sequences: A224189 A224190 A224191 * A224193 A224194 A224195

Keyword

nonn

Author

R. H. Hardin Apr 01 2013

Status

approved