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A220938 Equals two maps: number of 4Xn binary arrays indicating the locations of corresponding elements equal to exactly two of their horizontal and antidiagonal neighbors in a random 0..2 4Xn array 0
1, 37, 556, 9107, 172904, 2876430, 49406891 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Row 4 of A220935

LINKS

Table of n, a(n) for n=1..7.

EXAMPLE

Some solutions for n=3

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

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

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

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

CROSSREFS

Sequence in context: A006303 A219440 A219141 * A221292 A231514 A156226

Adjacent sequences:  A220935 A220936 A220937 * A220939 A220940 A220941

KEYWORD

nonn

AUTHOR

R. H. Hardin Dec 25 2012

STATUS

approved

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Last modified July 29 17:41 EDT 2021. Contains 346346 sequences. (Running on oeis4.)