A166816 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 increasing order.

0, 0, 105, 767, 3159, 9751, 25148, 57258, 118866, 229698, 419067, 729201, 1219361, 1970865, 3093142, 4730948, 7072884, 10361364, 14904189, 21087891, 29393019, 40411547, 54866592, 73634638, 97770470, 128535030

Offset

1,3

Links

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

Formula

Empirical: a(n)=(n^8+32*n^7+476*n^6+3038*n^5-1351*n^4-33082*n^3+46234*n^2-15348*n)/5040

Example

Some solutions for n=4
...1.3...1.4...1.3...1.1...1.5...1.3...1.1...2.4...1.2...1.2...1.3...1.4...1.3
...2.3...3.2...2.2...1.3...2.3...2.5...2.3...2.4...3.4...3.2...2.2...1.4...1.3
...4.4...3.2...2.2...2.4...4.4...4.4...3.3...2.5...5.4...4.2...4.5...2.4...2.3
...5.4...3.5...5.4...5.4...4.4...4.4...4.5...3.1...5.4...5.2...5.5...5.3...4.5
------
...2.5...1.5...2.3...1.2...1.2...1.3...1.5...1.4...1.3...2.5...1.5...1.3...1.4
...3.1...2.3...4.4...4.4...1.4...1.4...2.5...3.4...2.3...3.3...2.2...2.3...1.5
...3.4...3.3...5.1...5.3...1.4...4.4...4.3...4.4...4.3...4.1...2.2...3.3...2.2
...3.4...3.4...5.1...5.3...5.3...5.2...4.3...5.2...5.5...4.1...3.4...5.4...2.3

Crossrefs

Sequence in context: A078420 A152826 A133767 * A166798 A228303 A033593

Adjacent sequences: A166813 A166814 A166815 * A166817 A166818 A166819

Keyword

nonn

Author

R. H. Hardin Oct 21 2009

Status

approved