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#1 2010-07-30 04:49:31
- John E. Franklin
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- Registered: 2005-08-29
- Posts: 3,588
3 numbers in a row multiplied
2 x 3 x 4 = 24 and 3 x 3 x 3 = 27 and 27 - 3 = 24
3 x 4 x 5 = 60 and 4 x 4 x 4 = 64 and 64 - 4 = 60
1 x 2 x 3 = 6 and 2 x 2 x 2 = 8 and 8 - 2 = 6
4 x 5 x 6 = 120 and 5 x 5 x 5 = 125 and 125 - 5 = 120
This can be proven with the difference of two squares...
(n-1)(n)(n+1) = (n^2-1)n, which is n less than n^3.
igloo myrtilles fourmis
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