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 A180837 Number of nX3 arrays containing 3 indistinguishable copies of 1..n with rows and columns in lexicographically strictly increasing order 0

%I

%S 1,1,77,5385,545426,79230924,15755497776,4122239926855

%N Number of nX3 arrays containing 3 indistinguishable copies of 1..n with rows and columns in lexicographically strictly increasing order

%C Column 3 of A180839

%e Some solutions for 3X3

%e ..1..1..2....1..1..2....1..1..2....1..1..2....1..1..2....1..1..2....1..1..2

%e ..1..2..3....1..2..2....1..2..3....1..2..3....1..3..2....1..3..3....1..3..3

%e ..2..3..3....3..3..3....3..3..2....3..2..3....2..3..3....2..3..2....2..2..3

%e ...

%e ..1..1..2....1..1..2....1..1..2....1..1..3....1..1..3....1..1..3....1..1..3

%e ..1..3..2....1..3..2....1..3..3....1..2..2....1..2..3....1..2..3....1..2..2

%e ..3..3..2....3..2..3....3..2..2....2..3..3....2..3..2....2..2..3....3..3..2

%e ...

%e ..1..1..3....1..1..3....1..1..3....1..1..3....1..1..3....1..1..3....1..1..1

%e ..1..2..2....1..2..3....1..3..2....1..3..2....1..3..3....1..3..2....2..2..3

%e ..3..2..3....3..2..2....2..3..2....2..2..3....2..2..2....3..2..2....2..3..3

%e ...

%e ..1..1..2....1..1..2....1..1..2....1..1..2....1..1..2....1..1..2....1..1..2

%e ..2..3..1....2..3..1....2..3..1....2..3..2....2..3..2....2..3..3....2..3..3

%e ..2..3..3....3..3..2....3..2..3....3..3..1....3..1..3....3..1..2....3..2..1

%K nonn

%O 1,3

%A _R. H. Hardin_ Sep 20 2010

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Last modified August 11 09:58 EDT 2022. Contains 356065 sequences. (Running on oeis4.)