A184566 Number of (n+2)X3 0..3 arrays with each 3X3 subblock having rows and columns in lexicographically nondecreasing order

14178, 102445, 545662, 2430950, 9496395, 33351260, 107058241, 318063303, 883398416, 2312834051, 5747404508, 13634816674, 31030883261, 68030181122, 144179542873, 296289041222, 591935421670, 1152308627603, 2190104262402

Offset

1,1

Comments

Column 1 of A184574

Links

R. H. Hardin, Table of n, a(n) for n = 1..200

Formula

Empirical: a(n) = (1/121645100408832000)*n^19

+ (53/3201186852864000)*n^18

+ (5743/2134124568576000)*n^17

+ (12931/62768369664000)*n^16

+ (621041/62768369664000)*n^15

+ (10734523/31384184832000)*n^14

+ (1720232317/188305108992000)*n^13

+ (127448011/658409472000)*n^12

+ (6294370109/1931334451200)*n^11

+ (18970604773/438939648000)*n^10

+ (4321841102639/9656672256000)*n^9

+ (17491957547611/4828336128000)*n^8

+ (1086794057312713/47076277248000)*n^7

+ (2752481070552527/23538138624000)*n^6

+ (1237909924891457/2615348736000)*n^5

+ (1921023328483453/1307674368000)*n^4

+ (249101413506019/77189112000)*n^3

+ (12857906145353/2806876800)*n^2

+ (288855292519/77597520)*n

+ 561

Example

Some solutions for 4X3
..0..1..3....0..1..1....0..0..2....0..0..0....0..1..3....0..0..3....0..1..1
..0..2..3....0..1..2....0..1..2....1..1..3....0..3..3....0..1..3....1..1..1
..3..2..3....2..2..3....3..0..0....1..2..0....2..0..0....0..3..3....1..2..3
..3..3..1....2..3..1....3..3..1....3..0..0....3..1..3....2..0..1....2..1..0

Crossrefs

Sequence in context: A134610 A104825 A184574 * A184565 A251068 A184559

Adjacent sequences: A184563 A184564 A184565 * A184567 A184568 A184569

Keyword

nonn

Author

R. H. Hardin Jan 17 2011

Status

approved