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A220532 T(n,k)=Equals two maps: number of nXk binary arrays indicating the locations of corresponding elements equal to exactly two of their horizontal, vertical and antidiagonal neighbors in a random 0..3 nXk array 4
1, 1, 1, 2, 6, 2, 4, 27, 27, 4, 7, 107, 274, 107, 7, 12, 461, 2660, 2660, 461, 12, 21, 1844, 23948, 53150, 23948, 1844, 21, 37, 7502, 204634, 947486, 947486, 204634, 7502, 37, 65, 29893, 1697940, 15864668, 32675630, 15864668, 1697940, 29893, 65, 114, 119342 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,4

COMMENTS

Table starts

..1.....1.......2........4........7.......12........21.......37.....65.114

..1.....6......27......107......461.....1844......7502....29893.119342

..2....27.....274.....2660....23948...204634...1697940.13869434

..4...107....2660....53150...947486.15864668.258344332

..7...461...23948...947486.32675630

.12..1844..204634.15864668

.21..7502.1697940

.37.29893

.65

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..49

EXAMPLE

Some solutions for n=3 k=4

..1..0..1..1....0..0..1..1....0..0..0..0....1..1..0..0....0..1..1..1

..0..0..0..1....0..1..1..1....1..0..0..0....1..1..1..0....0..0..0..1

..0..0..0..0....1..1..1..1....0..1..1..0....1..1..0..0....1..0..1..1

CROSSREFS

Column 1 is A005251(n+1)

Sequence in context: A220430 A220279 A221188 * A060295 A102912 A064850

Adjacent sequences:  A220529 A220530 A220531 * A220533 A220534 A220535

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin Dec 15 2012

STATUS

approved

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Last modified February 29 05:25 EST 2020. Contains 332353 sequences. (Running on oeis4.)