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11:22 PM
hey @gimusi I got this solution
but I didn't quite understand
here $n_{c_n}$ is $\binom n {c_n}$
I don't know what does each $\binom n {c_n}$ count here?
 
11:38 PM
@LeylaAlkan I'll take a look! Probably tomorrow! Bye ;)
 

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