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Productive Numbers (Posted on 2013-05-26) Difficulty: 3 of 5
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    
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  Subject Author Date
Some Thoughts10-digit decimal numbersDej Mar2013-05-27 01:24:55
Solutioncomputer solution: the long list (spoilers)Charlie2013-05-26 14:58:35
Some Thoughtsre: WITH ZERO (more spoilers)Charlie2013-05-26 14:50:31
Some ThoughtsWITH ZEROAdy TZIDON2013-05-26 13:16:16
Some Thoughtsre: spoiler #1Charlie2013-05-26 12:48:16
Hints/Tipsspoiler #1Ady TZIDON2013-05-26 11:58:26
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