A185473 Number of (n+2)X7 0..2 arrays with each 3X3 subblock having rows and columns in lexicographically nondecreasing order

79743, 594798, 3097348, 12990375, 46410729, 146203201, 416227164, 1090826214, 2669230399, 6166331968, 13566979728, 28628817088, 58271012854, 114931139131, 220496274283, 412754753755, 755824704746, 1356767769574, 2391691228097

Offset

1,1

Comments

Column 5 of A185477

Links

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

Formula

Empirical: a(n) = (1/2155681382400)*n^17

+ (47/697426329600)*n^16

+ (611/134120448000)*n^15

+ (33559/174356582400)*n^14

+ (189341/33210777600)*n^13

+ (178309/1277337600)*n^12

+ (147904279/44706816000)*n^11

+ (87015563/1219276800)*n^10

+ (11642696389/9754214400)*n^9

+ (69578815777/4877107200)*n^8

+ (3848584871/32256000)*n^7

+ (44384094767/63866880)*n^6

+ (247986427893683/87178291200)*n^5

+ (124742663704661/14529715200)*n^4

+ (1115145293971/58212000)*n^3

+ (2731472131849/100900800)*n^2

+ (9965552297/510510)*n

+ 1735

Example

Some solutions for 4X7
..0..0..0..0..0..0..0....0..0..0..0..0..1..1....0..0..0..0..0..0..1
..0..0..0..0..0..2..2....0..0..0..0..0..1..2....0..0..0..0..1..1..2
..0..0..0..1..1..0..1....0..0..0..0..1..0..0....0..0..0..1..1..1..2
..0..1..1..2..2..1..2....0..0..2..2..1..0..2....0..1..1..2..1..2..1

Crossrefs

Sequence in context: A238177 A237172 A146324 * A235075 A229700 A112785

Adjacent sequences: A185470 A185471 A185472 * A185474 A185475 A185476

Keyword

nonn

Author

R. H. Hardin Jan 28 2011

Status

approved