A166836 - OEIS

A166836

Number of nX4 1..4 arrays containing at least one of each value, all equal values connected, rows considered as a single number in nondecreasing order, and columns considered as a single number in nonincreasing order.

1, 219, 3170, 23464, 124843, 538072, 1990990

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

OFFSET

1,2

LINKS

Table of n, a(n) for n=1..7.

EXAMPLE

Some solutions for n=3

...3.2.2.2...3.2.2.2...4.3.1.1...2.2.1.1...2.2.1.1...3.1.1.1...2.1.1.1

...3.3.3.1...3.4.2.1...4.3.4.2...4.2.2.1...2.2.4.4...3.2.1.1...2.2.2.2

...4.4.3.3...3.4.2.2...4.4.4.4...4.2.3.1...3.2.4.4...3.4.1.1...4.3.2.2

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...3.3.2.1...3.3.2.2...2.2.1.1...2.1.1.1...2.2.1.1...2.2.2.2...4.3.3.3

...3.3.2.2...4.3.3.1...4.3.3.1...4.3.1.1...2.2.4.3...4.3.2.1...4.4.1.1

...3.3.4.2...4.4.1.1...4.4.4.1...4.3.3.3...2.2.4.4...4.3.2.1...4.4.2.2

CROSSREFS

Sequence in context: A256815 A179580 A043435 * A200827 A286441 A285889

Adjacent sequences: A166833 A166834 A166835 * A166837 A166838 A166839

KEYWORD

nonn

AUTHOR

R. H. Hardin Oct 21 2009

STATUS

approved