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A164756
Number of nX4 1..4 arrays with all 1s connected, all 2s connected, all 3s connected, all 4s connected, 1 in the upper left corner, 2 in the upper right corner, 3 in the lower left corner, 4 in the lower right corner, and with no element having more than 2 neighbors with the same value
0
25, 258, 739, 1538, 2570, 3742, 4930, 6222, 7670, 9240, 10946, 12778, 14742, 16836
OFFSET
2,1
EXAMPLE
Some solutions for n=3
...1.1.4.2...1.2.2.2...1.1.2.2...1.3.2.2...1.1.2.2...1.3.3.2...1.1.3.2
...1.1.4.2...1.1.4.2...3.4.2.4...3.3.2.4...1.1.2.4...3.3.2.2...1.1.3.4
...3.3.4.4...3.3.4.4...3.4.4.4...3.4.4.4...3.3.4.4...3.4.4.4...3.3.3.4
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...1.3.2.2...1.1.2.2...1.2.2.2...1.1.2.2...1.2.2.2...1.2.2.2...1.1.2.2
...1.3.4.2...1.4.4.4...3.2.3.4...3.3.4.2...1.1.1.4...2.2.3.2...1.2.2.4
...3.3.4.4...3.3.3.4...3.3.3.4...3.3.4.4...3.4.4.4...3.3.3.4...3.4.4.4
CROSSREFS
Sequence in context: A298068 A017450 A264267 * A221781 A298717 A058482
KEYWORD
nonn
AUTHOR
R. H. Hardin Aug 24 2009
STATUS
approved