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A166799 Number of nX2 1..6 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 nondecreasing order. 0
0, 0, 90, 1552, 9902, 41152, 133181, 364793, 885880, 1963116, 4046800, 7865858, 14559622, 25856844, 44314491, 73631219, 119053056, 187891752, 290179494 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..19.

FORMULA

From G. C. Greubel, May 26 2016: (Start)

Empirical a(n) = (1/226800)*(n-1)*(n-2)*(n^8 + 53*n^7 + 1477*n^6 + 23435*n^5 + 173779*n^4 + 177842*n^3 - 1867077*n^2 + 450450*n - 113400).

Empirical G.f.: -x^3*(x^8 + 54*x^7 - 248*x^6 + 88*x^5 + 1261*x^4 - 2740*x^3 + 2220*x^2 - 562*x - 90)/(1-x)^11.

Empirical E.g.f.: (1/226800)*(-226800 + 226800*x - 113400*x^2 + 3439800*x^3 + 11254950*x^4 + 5751270*x^5 + 1013985*x^6 + 85050*x^7 + 3870*x^8 + 95*x^9 + x^10)*exp(x) + 1. (End)

EXAMPLE

Some solutions for n=4

...1.2...1.3...1.1...2.3...1.5...1.5...1.4...1.1...1.1...1.1...1.4...2.6...2.3

...1.2...2.2...2.5...4.3...2.2...2.5...4.4...1.5...3.6...2.4...3.3...2.6...4.1

...4.6...4.2...3.4...5.3...2.3...2.6...5.3...2.3...4.6...3.6...5.2...3.1...4.1

...5.3...6.5...6.4...6.1...4.6...4.3...6.2...6.4...5.2...5.6...6.6...4.5...5.6

------

...1.3...1.1...2.4...1.2...1.1...1.4...1.2...3.6...1.6...2.2...1.4...1.5...1.2

...5.3...4.5...2.5...4.6...1.6...1.4...1.6...4.1...3.2...3.4...6.2...2.5...3.2

...5.4...6.2...3.1...5.3...2.5...3.2...4.3...4.4...4.2...3.6...6.3...4.5...5.4

...6.2...6.3...3.6...5.5...3.4...5.6...4.5...5.2...4.5...5.1...6.5...6.3...6.6

CROSSREFS

Sequence in context: A250869 A234983 A166817 * A001561 A296998 A060094

Adjacent sequences: A166796 A166797 A166798 * A166800 A166801 A166802

KEYWORD

nonn

AUTHOR

R. H. Hardin, Oct 21 2009

STATUS

approved

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Last modified January 26 22:13 EST 2023. Contains 359836 sequences. (Running on oeis4.)