A185474 Number of (n+2) X 8 0..2 arrays with each 3 X 3 subblock having rows and columns in lexicographically nondecreasing order.

169052, 1433903, 8297059, 37961900, 146203201, 493061605, 1497314456, 4179700035, 10893560939, 26828743607, 63022511852, 142244535949, 310251195820, 656871055669, 1354738985131, 2729104397743, 5381326476837

Offset: 1

Author

R. H. Hardin, Jan 28 2011

Keywords

• nonn

Comments

Column 6 of A185477.

Examples

			Some solutions for 4 X 8
..0..0..0..0..0..0..0..1....0..0..0..0..0..0..0..0....0..0..0..0..0..0..0..2
..0..0..0..0..0..0..1..1....0..0..0..0..1..1..2..2....0..0..0..0..0..0..2..2
..0..0..0..0..0..1..0..2....0..0..0..2..1..2..1..2....0..0..0..0..0..1..0..1
..0..0..0..0..2..1..2..1....0..0..0..2..1..2..2..0....0..0..1..1..1..2..1..1
		

Links

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

Crossrefs

Cf. A185477.

Formula

Empirical: a(n) = (1/212666259456000)*n^19

+ (67/83147710464000)*n^18

+ (12559/194011324416000)*n^17

+ (12833/3923023104000)*n^16

+ (333169/2853107712000)*n^15

+ (196437919/62768369664000)*n^14

+ (1153058911/17118646272000)*n^13

+ (1339332949/1034643456000)*n^12

+ (28852162981/1207084032000)*n^11

+ (350922659539/877879296000)*n^10

+ (4735468557467/877879296000)*n^9

+ (11975048873639/219469824000)*n^8

+ (131882024236729/329204736000)*n^7

+ (7064899018536199/3362591232000)*n^6

+ (1862906706349061/237758976000)*n^5

+ (13955757767803297/653837184000)*n^4

+ (26671169520943/623750400)*n^3

+ (851721864110749/15437822400)*n^2

+ (4258571767339/116396280)*n

+ 2793.