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A221186 Equals two maps: number of nX3 binary arrays indicating the locations of corresponding elements equal to exactly two of their horizontal, vertical and antidiagonal neighbors in a random 0..2 nX3 array 1
2, 27, 274, 2648, 23765, 203122, 1686374, 13787513, 111630017, 898826748, 7215684025, 57832318493, 463108937837, 3706758773474, 29661932054299, 237327986894765, 1898757328855273, 15190598160183104, 121526907452205194 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A221188

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..190

EXAMPLE

Some solutions for n=3

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

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

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

CROSSREFS

Sequence in context: A302174 A195604 A011543 * A220530 A199021 A091709

Adjacent sequences:  A221183 A221184 A221185 * A221187 A221188 A221189

KEYWORD

nonn

AUTHOR

R. H. Hardin Jan 04 2013

STATUS

approved

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Last modified January 21 16:54 EST 2020. Contains 331114 sequences. (Running on oeis4.)