Puzzle: Kth number with only prime factors 3,5,7.

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Design an algorithm to find the kth number  such that the only prime factors are 3,5, and 7.
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By  Vineet JhunJhunwala





Sangeeta Haldhar Sangeeta Haldhar   11 years ago

3=2*1+1,
5=2*2+1,
7=2*3+1
So,Kth element is:-
2K+1

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Abhishek Gupta Abhishek Gupta   10 years ago

11=2*5+1

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