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A220373 Equals two maps: number of nX3 binary arrays indicating the locations of corresponding elements equal to exactly two of their horizontal and vertical neighbors in a random 0..2 nX3 array 1
2, 23, 236, 2095, 18296, 154562, 1280878, 10492879, 85253117, 688997802, 5548695509, 44580367227, 357622113010, 2865892548630, 22950987106487, 183716756194773, 1470171909243331, 11762592622678971, 94098427741015878 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A220375

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..48

EXAMPLE

Some solutions for n=3

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

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

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

CROSSREFS

Sequence in context: A019518 A048677 A132933 * A220428 A110773 A088087

Adjacent sequences:  A220370 A220371 A220372 * A220374 A220375 A220376

KEYWORD

nonn

AUTHOR

R. H. Hardin Dec 13 2012

STATUS

approved

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Last modified December 8 20:37 EST 2021. Contains 349596 sequences. (Running on oeis4.)