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Let"s have a 3xn matrice with the following properties:
The firs row of the matrice is 1,2,3,... ,n in this order.
The second and the third rows are permutations of the first.
Very important, that in each column thera are different entries.
How many matrices with thees properties are there?
The answer for 2xn matrices is well-known, but what is the answer for 3xn, or for kxn ( k<=n) ?
The firs row of the matrice is 1,2,3,... ,n in this order.
The second and the third rows are permutations of the first.
Very important, that in each column thera are different entries.
How many matrices with thees properties are there?
The answer for 2xn matrices is well-known, but what is the answer for 3xn, or for kxn ( k<=n) ?