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Go count (Posted on 2012-12-11) Difficulty: 2 of 5
Consider a matrix nXn representing a multiplication table i.e. aij=i*j .
Determine the number of appearances of n in this matrix.

No Solution Yet Submitted by Ady TZIDON    
Rating: 5.0000 (1 votes)

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Solution Solution | Comment 4 of 6 |

Let D equal the number of distinct divisors or n.

If the nxn matrix is a0 0 to an-1 n-1, then the number of times n appears in the table, for n > 1, is D - 2. (For n = 0 nad n = 1, the number of times n appears in the table is 0.)

If the nxn matrix is a1 1 to an n, then the number of times n appears in the table is D + 2n.
  Posted by Dej Mar on 2012-12-12 00:29:15
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