Could you help with this question as it has me stumped!

Solve for "N"




Like a number of 'puzzlers' this is designed so you do NOT just use some standard algorithm. It is about patterns - ways of 'seeing' the pieces. Let me try to show you what I 'see':

12N (N-1)/2 = N(N-1)(N-2)...

Now, I know, from experience, that I should try to make the pieces look as much alike as possible, so I can focus on the differences:

N(N-1)6 = N(N-1)(N-2)...

I can make things look even more alike:

N(N-1)321 = N(N-1)[(N-2)!]

[That is based on recognizing that 6 is a factorial - something that also comes from experience and playing around.] I imagine you can see one answer already. The only other question would be - is it the only answer? I think if you play around with the shapes, say looking at the curves for the two functions on the two sides, you will see that they only cross 1 time - so you cannot be missing a second (positive) solution.



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