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 Productive Numbers (Posted on 2013-05-26)
Find all possible 9-digit numbers using precisely nine distinct digits from 0 to 9 such that each pair of consecutive digits is the product of two single-digit numbers.

For example, 2 and 1 can appear next to each other since 3*7=21. However, 2 and 6 cannot appear next to each other since 26 is the product only of 2 and 13 (and 1 and 26), and each pair of factors contains a number that is not a single-digit number.

*** None of the 9-digit numbers can contain any leading zero.

 No Solution Yet Submitted by K Sengupta No Rating

Comments: ( Back to comment list | You must be logged in to post comments.)
 re: WITH ZERO (more spoilers) | Comment 4 of 6 |

If one limits the possibility of zero to being at the end, there are four possibilities:

724815630
725481630
728145630
728163540

 Posted by Charlie on 2013-05-26 14:50:31

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