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

2,1

LINKS

Table of n, a(n) for n=2..15.

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

------

...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

Adjacent sequences:  A164753 A164754 A164755 * A164757 A164758 A164759

KEYWORD

nonn

AUTHOR

R. H. Hardin Aug 24 2009

STATUS

approved

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Last modified October 2 06:43 EDT 2022. Contains 357191 sequences. (Running on oeis4.)