A164758 - OEIS

A164758

Number of nX6 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

83, 644, 2570, 6742, 13654, 24738

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OFFSET

2,1

LINKS

Table of n, a(n) for n=2..7.

EXAMPLE

Some solutions for n=3

...1.1.3.3.2.2...1.1.1.1.2.2...1.1.3.3.2.2...1.2.2.2.2.2...1.1.1.1.2.2

...3.1.1.3.4.2...3.3.3.1.2.4...3.1.1.3.4.4...1.2.4.4.4.4...3.3.3.3.3.3

...3.3.3.3.4.4...3.4.4.4.4.4...3.3.3.3.4.4...3.3.3.3.3.4...3.4.4.4.4.4

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