2010年Puzzleup数学竞赛−第16题: Generating 9-Letter Codes

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Generating 9-Letter Codes

You will generate 9-letter codes changing the places of letters in the word TRANSFORM.

The condition is that none of the letters in the generated codes will be on the same place as they were on the word TRANSFORM.

How many different codes can be generated?

Example: If the same question was asked for 4-letter codes with the letters of the word DATA, the answer would be 2: ADAT, ATAD.