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OT: one of the guets said, "Personal referrals are very important for recruiting. We try and get each engineer to refer 2 people. 2^n scales very well. You get great people, but also get to stay under the radar"

I don't understand how he gets 2^n. anyone else?

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You get 2^n - 1 which is what he means by scaling 2^n. That's because the (sum of numbers 2^k for k = 0 to n - 1) = 2^n - 1.

Example: if you have one, she hires 2, those 2 hire 2 each. You have 1+2+4 = 7 = 8 - 1 = 2^3 - 1

n here is "generation". Start with one engineer, n=0. They refer 2, n=1. They each refer 2, referring a total of 4, n=2. Etc.

(It works out such that the total number of people follows the same curve. Think of the total number of engineers as (2^n)-1: following the same example above, one engineer is then n=1, three total is n=2, seven total is n=3.)

Okay, the generations makes sense. Thanks!

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