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A220961 Equals two maps: number of 4Xn binary arrays indicating the locations of corresponding elements equal to exactly two of their horizontal, diagonal and antidiagonal neighbors in a random 0..3 4Xn array 0
1, 94, 1224, 33708, 627760, 11214779, 190881959 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Row 4 of A220959

LINKS

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

EXAMPLE

Some solutions for n=3

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

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

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

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

CROSSREFS

Sequence in context: A093294 A107613 A220797 * A218648 A278321 A189414

Adjacent sequences:  A220958 A220959 A220960 * A220962 A220963 A220964

KEYWORD

nonn

AUTHOR

R. H. Hardin Dec 26 2012

STATUS

approved

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Last modified January 21 18:06 EST 2019. Contains 319349 sequences. (Running on oeis4.)