Advent calendar 2017
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Sunday afternoon maths LXIV
Is it equilateral?Cube multiples
Advent calendar 2017
Sunday afternoon maths LXII
What's the star?Sunday afternoon maths LXI
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Pick a three digit number whose digits are all different.
Sort the digits into ascending and descending order to form two new numbers. Find the difference between these numbers.
Repeat this process until the number stops changing. The final result is today's number.