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 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, 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 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 LINKS 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

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Last modified December 6 12:26 EST 2022. Contains 358634 sequences. (Running on oeis4.)