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A164753 Number of n X n 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
1, 80, 739, 3496, 13654 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,2

LINKS

Table of n, a(n) for n=2..6.

EXAMPLE

Some solutions for n=4

...1.1.1.2...1.2.2.2...1.1.1.2...1.1.2.2...1.3.2.2...1.1.1.2...1.1.2.2

...1.4.4.2...1.1.4.4...1.2.2.2...3.1.2.4...1.3.2.4...1.2.2.2...3.1.4.2

...1.3.4.2...3.1.1.4...1.1.3.3...3.1.1.4...3.3.2.4...1.3.3.3...3.1.4.2

...3.3.4.4...3.3.3.4...3.3.3.4...3.3.3.4...3.4.4.4...3.3.4.4...3.1.4.4

------

...1.2.2.2...1.1.1.2...1.2.2.2...1.1.2.2...1.3.2.2...1.1.2.2...1.4.2.2

...1.1.1.4...1.3.1.2...1.4.4.4...1.2.2.3...1.3.4.2...1.4.4.2...3.4.2.2

...3.4.1.4...3.3.1.1...1.1.1.4...2.2.3.3...1.3.4.2...3.4.2.2...3.4.4.4

...3.4.4.4...3.4.4.4...3.3.4.4...3.3.3.4...3.3.4.4...3.4.4.4...3.3.3.4

CROSSREFS

Sequence in context: A204342 A235090 A211693 * A279745 A062911 A024392

Adjacent sequences:  A164750 A164751 A164752 * A164754 A164755 A164756

KEYWORD

nonn

AUTHOR

R. H. Hardin Aug 24 2009

STATUS

approved

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Last modified May 23 03:10 EDT 2019. Contains 323507 sequences. (Running on oeis4.)