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A220959
T(n,k)=Equals two maps: number of nXk binary arrays indicating the locations of corresponding elements equal to exactly two of their horizontal, diagonal and antidiagonal neighbors in a random 0..3 nXk array
4
1, 1, 1, 2, 6, 1, 4, 19, 23, 1, 7, 76, 142, 94, 1, 12, 267, 1769, 1224, 380, 1, 21, 1074, 15640, 33708, 9500, 1494, 1, 37, 4069, 135445, 627760, 590009, 74689, 5939, 1, 65, 15916, 1135785, 11214779
OFFSET
1,4
COMMENTS
Table starts
.1....1.....2......4......7.......12......21....37.65
.1....6....19.....76....267.....1074....4069.15916
.1...23...142...1769..15640...135445.1135785
.1...94..1224..33708.627760.11214779
.1..380..9500.590009
.1.1494.74689
.1.5939
.1
EXAMPLE
Some solutions for n=3 k=4
..0..0..0..0....1..0..0..1....0..1..1..1....0..1..1..0....0..1..0..0
..0..0..1..0....1..0..0..0....0..1..0..1....0..0..0..1....0..0..1..0
..1..1..0..0....0..0..1..0....0..0..1..0....0..0..1..1....1..0..1..1
CROSSREFS
Column 2 is A220372
Row 1 is A005251(n+1)
Row 2 is A220795
Sequence in context: A220406 A372261 A220794 * A360598 A243434 A265416
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin Dec 26 2012
STATUS
approved