metageek.livejournal.com ([identity profile] metageek.livejournal.com) wrote in [personal profile] petmoosie 2009-07-13 01:56 am (UTC)

Yes, and yes

Let's see here...

N = ∑3 ≤ i ≤ 30 20i

N = 2021 ≤ i ≤ 28 20i

Now, the next step involves knowing that (x-1)(xn + xn-1 + … x1 + 1) = xn+1-1. So we have:

N = 202 (2029-1)/(20-1)

...which comes out to 11,302,545,200. Not even a trillion.


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