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URL: https://oeis.org/A185903

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A185903
T(n,k)=1/8 the number of nXk 0..7 arrays with every element equal to exactly one or two of its horizontal and vertical neighbors.
4
0, 1, 1, 1, 15, 1, 8, 196, 196, 8, 15, 2765, 7854, 2765, 15, 71, 38731, 546280, 546280, 38731, 71, 176, 545328, 28967421, 139230658, 28967421, 545328, 176, 673, 7675381, 1748982326, 32611077940, 32611077940, 1748982326, 7675381, 673, 1905
OFFSET
1,5
COMMENTS
Table starts
....0.........1...........1.............8.............15............71
....1........15.........196..........2765..........38731........545328
....1.......196........7854........546280.......28967421....1748982326
....8......2765......546280.....139230658....32611077940.7921723799549
...15.....38731....28967421...32611077940.30884279980274
...71....545328..1748982326.7921723799549
..176...7675381.98953708266
..673.108065699
.1905
EXAMPLE
Some solutions for 4X3 with a(1,1)=0
..0..4..5....0..0..4....0..4..0....0..0..6....0..4..2....0..4..6....0..0..3
..0..4..5....4..4..4....0..4..0....4..4..6....0..4..2....0..4..6....4..0..3
..1..1..4....6..7..3....6..6..0....4..4..5....5..3..3....2..0..0....4..0..0
..1..1..4....6..7..3....5..5..0....3..3..5....5..5..5....2..5..5....4..4..4
CROSSREFS
Column 1 is A015442(n-1)
Sequence in context: A040235 A040236 A331019 * A040237 A317835 A225762
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Feb 06 2011
STATUS
approved