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A186180
T(n,k)=Number of (n+2)X(k+2) 0..5 arrays with each 3X3 subblock having rows and columns in lexicographically nondecreasing order
10
520017, 10084236, 10084236, 143369699, 311128593, 143369699, 1662436696, 6520730198, 6520730198, 1662436696, 16382439469, 105970767207, 188034884094, 105970767207, 16382439469, 140871930232, 1414199542732, 4041778238254
OFFSET
1,1
COMMENTS
Table starts
..........520017..........10084236............143369699............1662436696
........10084236.........311128593...........6520730198..........105970767207
.......143369699........6520730198.........188034884094.........4041778238254
......1662436696......105970767207........4041778238254.......111203560772547
.....16382439469.....1414199542732.......69471558136868......2391923493659465
....140871930232....16059530994398......995828085723859.....42174821764604242
...1078197169699...159099595031390....12251749347425002....629512200937395977
...7459396065112..1400823449171621...132151619698400257...8143852416376007571
..47221234070168.11121210203531892..1270399513311212137..92981285763140685886
.276218909139304.80539662788823416.11027904404610778911.950506396177707075676
FORMULA
Empirical: T(n,k) is a polynomial of degree 5k+50 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..0....0..0..0..0....0..0..0..0....0..0..0..0....0..0..0..0
..0..0..0..0....0..0..0..0....0..0..0..0....0..0..0..0....0..0..0..0
..0..0..0..3....0..0..0..0....0..0..0..0....0..0..0..3....0..0..0..0
..0..0..0..5....0..0..1..2....0..1..1..4....0..1..5..1....0..0..2..3
..0..1..1..0....1..2..0..2....3..1..4..1....5..4..4..5....0..2..5..1
CROSSREFS
Sequence in context: A251834 A157803 A236095 * A186172 A186171 A251043
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, General degree formula intuited by D. S. McNeil in the Sequence Fans Mailing List, Feb 13 2011
STATUS
approved