The number of numbers that can be formed by using the digits 1,2,3,3,3,2,1 so that odd digits always occupy odd palces is
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3 Answers
Lokesh Verma
·2008-11-01 01:18:40
1 digit: 2 ways
2 digit: 2.1 way (even digit can only be filled by 2!)
3 digit: 2.1.2 ways
4 digit: 2.1.2.1 ways
5 digit: 3 odd spaces..
case (all 3's): 1 way
case (2 3's): 3 ways
case (1 3's): 3 ways
Total = 7
Take sum...
Lokesh Verma
·2008-11-01 07:00:34
1
3
12
32
121
123
321
323
1212
1232
3212
3232
12123
12321
12323
32121
32123
32321
32323
These are 19!