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A230739
T(n,k)=Number of (n+3)X(k+3) 0..2 black 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
6
2, 8, 8, 30, 66, 30, 102, 244, 244, 102, 348, 2016, 2106, 2016, 348, 1172, 6576, 16536, 16536, 6576, 1172, 3956, 54138, 130446, 320970, 130446, 54138, 3956, 13326, 173428, 1025430, 2382398, 2382398, 1025430, 173428, 13326, 44916, 1427040, 8053490
OFFSET
1,1
COMMENTS
Table starts
.....2.......8.......30........102..........348...........1172.............3956
.....8......66......244.......2016.........6576..........54138...........173428
....30.....244.....2106......16536.......130446........1025430..........8053490
...102....2016....16536.....320970......2382398.......46599682........342031378
...348....6576...130446....2382398.....43853402......801845362......14669811856
..1172...54138..1025430...46599682....801845362....36695929036.....625553036008
..3956..173428..8053490..342031378..14669811856...625553036008...26681634560690
.13326.1427040.63237238.6692078688.268320990890.28644012159382.1137681116923966
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=3 k=4
..x..0..x..0..x..2..x....x..0..x..2..x..2..x....x..0..x..0..x..1..x
..1..x..1..x..1..x..0....2..x..1..x..0..x..1....1..x..1..x..2..x..0
..x..2..x..0..x..1..x....x..0..x..1..x..1..x....x..2..x..0..x..2..x
..1..x..0..x..2..x..0....1..x..0..x..2..x..0....1..x..0..x..2..x..0
..x..2..x..1..x..1..x....x..2..x..0..x..2..x....x..2..x..1..x..1..x
..1..x..1..x..0..x..0....1..x..2..x..1..x..1....1..x..0..x..0..x..0
CROSSREFS
Column 1 is A230701
Column 3 is A230703
Column 5 is A230705
Column 7 is A230707
Sequence in context: A250313 A180825 A230708 * A227326 A323852 A064231
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Oct 28 2013
STATUS
approved