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January 14th, 2019, 01:46 PM   #11
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Math Focus: Number Theory, Algebraic Geometry
Quote:
Originally Posted by Denis View Post
Start from T to N: how many ways?
You should get 10.
Now you're finished: answer is 20.
Why?
Because going from N to R requires the same steps.
You can't just add the number of ways of going from T to N to the number of ways to go from N to R. Consider the trivial version of this problem where the picture is just:

T - H - I - N - K - E - R

Here, there is 1 way to go from T to N, and 1 way to go from N to R. But that doesn't mean there are 1 + 1 = 2 ways to go from T to R.

(Also, for what it's worth, there are 2^3 = 8 ways to go from T to N.)
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January 14th, 2019, 02:51 PM   #12
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Looks like you don't appreciate my THINKERing
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January 15th, 2019, 09:03 AM   #13
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Code:
T   H  I   N  K   E  R   
   21     42     61

1     32     52      7

   22     43     62
I finally "see" the simplicity!

1 21 32 42 52 61 7

1 22 32 43 52 62 7

Thanks CJEM.
Was trying to impress Miss ProofOfALifeTime
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