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A166827 Number of nX2 1..5 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. 0
0, 0, 55, 478, 2167, 7125, 19234, 45351, 96802, 191358, 355785, 629068, 1066417, 1744171, 2765724, 4268605, 6432852, 9490828, 13738635, 19549290, 27387835, 37828561, 51574534, 69479619, 92573206, 122087850 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..26.

FORMULA

Empirical: a(n)=(n^8+32*n^7+420*n^6+1862*n^5-4431*n^4-23002*n^3+59450*n^2-39372*n+5040)/5040

EXAMPLE

Some solutions for n=4

...1.1...3.1...1.1...2.1...3.3...3.1...2.2...3.2...1.1...4.1...2.1...3.3...2.1

...2.2...3.5...2.1...2.2...3.3...3.2...3.2...3.4...2.1...4.2...3.3...4.2...2.4

...3.2...3.5...3.3...2.3...4.1...4.4...3.5...4.4...3.3...4.2...4.3...4.2...2.5

...5.4...4.2...5.4...5.4...5.2...5.4...4.1...5.1...4.5...5.3...5.3...5.1...3.3

------

...3.2...3.3...2.2...2.2...2.1...3.2...1.1...3.1...3.1...3.2...3.3...3.1...3.1

...3.4...4.2...3.1...3.1...2.3...5.1...3.3...4.2...3.5...3.3...4.1...3.1...3.2

...5.1...5.1...4.1...3.3...4.3...5.1...4.2...4.2...4.2...5.1...5.2...4.1...3.2

...5.5...5.5...5.5...5.4...4.5...5.4...5.2...5.2...4.4...5.4...5.2...5.2...5.4

CROSSREFS

Sequence in context: A116060 A145054 A166839 * A266035 A241699 A262103

Adjacent sequences:  A166824 A166825 A166826 * A166828 A166829 A166830

KEYWORD

nonn

AUTHOR

R. H. Hardin Oct 21 2009

STATUS

approved

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Last modified June 29 23:00 EDT 2022. Contains 354913 sequences. (Running on oeis4.)