A220244 - OEIS

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A220244

Equals two maps: number of nX3 binary arrays indicating the locations of corresponding elements equal to exactly two of their king-move neighbors in a random 0..1 nX3 array

2, 18, 143, 816, 4467, 27192, 158296, 915920, 5443662, 31825008, 185788218, 1094039664, 6406886173, 37509117127, 220173740293, 1290097909772, 7558886967916, 44324041325721

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

COMMENTS

Column 3 of A220247

LINKS

Table of n, a(n) for n=1..18.

EXAMPLE

Some solutions for n=3

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

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

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