A203535 Number of n X n 0..2 arrays with every element neighboring horizontally or vertically both a 0 and a 1.
0, 4, 72, 3364, 1700580, 3743237124, 44312000955508, 2752746090434507556, 840982281825673724760300, 1273642755637661083775996170564
Offset: 1
Keywords
Examples
Some solutions for n=5 ..0..1..2..0..1....1..1..0..0..0....2..1..0..0..2....0..0..1..0..1 ..0..1..2..0..1....0..2..2..1..1....0..1..2..1..1....1..1..1..0..1 ..2..1..2..0..2....0..2..1..0..1....0..1..1..2..0....1..0..1..0..0 ..1..0..0..1..0....1..1..1..0..0....1..2..0..2..0....0..0..1..0..1 ..1..0..1..1..0....1..0..0..1..1....1..0..0..1..1....2..1..1..0..1
Crossrefs
Cf. A203542.
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