OFFSET
1,1
COMMENTS
Table starts
...45...89..147...220...309....415....539....682.....845....1029....1235
...89..193..340...537...792...1114...1513...2000....2587....3287....4114
..147..340..631..1048..1627...2413...3461...4837....6619....8898...11779
..220..537.1048..1837..3024...4774...7307..10909...15944...22867...32238
..309..792.1627..3024..5313...8989..14767..23648...36997...56634...84939
..415.1114.2413..4774..8989..16345..28844..49489...82648..134509..213640
..539.1513.3461..7307.14767..28844..54543..99872..177207..305112..510719
..682.2000.4837.10909.23648..49489..99872.194245..364432..660821.1160932
..845.2587.6619.15944.36997..82648.177207.364432..719905.1369596.2516995
.1029.3287.8898.22867.56634.134509.305112.660821.1369596.2725367.5225554
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..9378
R. H. Hardin, Polynomials for columns 1-8
FORMULA
Empirical: T(n,k) is a polynomial of degree k+2 in n, for fixed k.
Let T(n,k,z) be the number of (n+2)X(k+2) 0..z arrays with each 3X3 subblock having rows and columns in lexicographically nondecreasing order.
Then empirically T(n,k,z) is a polynomial of degree z*k + z*(z+1)*(z+5)/6 in n, for fixed k.
EXAMPLE
Some solutions for 5X4
..0..0..0..1....0..0..0..1....0..0..0..0....0..0..0..1....0..0..0..0
..0..0..1..1....0..0..0..1....0..0..0..0....0..0..1..1....0..0..0..0
..0..0..1..1....0..0..1..1....0..0..0..0....0..0..1..1....0..0..0..0
..0..1..0..0....0..1..0..1....0..0..0..1....0..1..1..1....0..0..1..1
..1..1..0..0....1..1..0..1....1..1..1..0....0..1..1..1....1..1..0..1
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, general degree formula intuited by D. S. McNeil in the Sequence Fans Mailing List, Jan 16 2011
STATUS
approved