- #1
TranscendArcu
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Find an expression that is identical to [itex]\sum_{k=0}^n \binom{3n}{3k}[/itex]
According to Wolfram, the correct solution to this is: [itex] \frac{1}{3} \left(2(-1)^n + 8^n\right)[/itex]
But I'm not sure which identities of the binomial coefficient I'm supposed to use to prove this. Can anyone give me some direction?
Thanks!
According to Wolfram, the correct solution to this is: [itex] \frac{1}{3} \left(2(-1)^n + 8^n\right)[/itex]
But I'm not sure which identities of the binomial coefficient I'm supposed to use to prove this. Can anyone give me some direction?
Thanks!