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A230708
T(n,k)=Number of (n+3)X(k+3) 0..2 white square subarrays x(i,j) with each element diagonally or antidiagonally next to at least one element with value (x(i,j)+1) mod 3, and upper left element zero
10
2, 8, 8, 30, 28, 30, 102, 244, 244, 102, 348, 800, 2106, 800, 348, 1172, 6576, 16536, 16536, 6576, 1172, 3956, 21076, 130446, 121382, 130446, 21076, 3956, 13326, 173428, 1025430, 2382398, 2382398, 1025430, 173428, 13326, 44916, 554040, 8053490
OFFSET
1,1
COMMENTS
Table starts
.....2......8.......30........102..........348...........1172.............3956
.....8.....28......244........800.........6576..........21076...........173428
....30....244.....2106......16536.......130446........1025430..........8053490
...102....800....16536.....121382......2382398.......17497342........342031378
...348...6576...130446....2382398.....43853402......801845362......14669811856
..1172..21076..1025430...17497342....801845362....13663471254.....625553036008
..3956.173428..8053490..342031378..14669811856...625553036008...26681634560690
.13326.554040.63237238.2508344646.268320990890.10652997961328.1137681116923966
LINKS
FORMULA
Empirical for column k:
k=1: a(n) = 3*a(n-1) +3*a(n-2) -6*a(n-3) +a(n-5)
k=2: a(n) = 31*a(n-2) -126*a(n-4) +42*a(n-6) +79*a(n-8) -a(n-10) +8*a(n-12)
k=3: [order 22]
k=4: [order 50]
EXAMPLE
Some solutions for n=2 k=4
..0..x..2..x..2..x..0....0..x..2..x..2..x..2....0..x..0..x..2..x..0
..x..1..x..0..x..1..x....x..1..x..0..x..0..x....x..1..x..0..x..1..x
..0..x..1..x..2..x..0....0..x..0..x..1..x..2....1..x..2..x..1..x..1
..x..2..x..0..x..1..x....x..2..x..2..x..1..x....x..2..x..1..x..2..x
..1..x..1..x..0..x..0....1..x..1..x..0..x..0....1..x..0..x..0..x..1
CROSSREFS
Sequence in context: A146749 A250313 A180825 * A230739 A227326 A323852
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Oct 28 2013
STATUS
approved