2

After some research, I cannot find a solution to this very basic question:

What is the sum of a constant over a domain (of a variable X): $$\sum_{X \in \{0,1\}} 1 = ??$$

I would say that the result is $2$ but I am not sure.

Thanks by advance

Aymeric

shp
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ailauli69
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  • You are summing over the reals? But any sum of uncountably many positive terms diverges. In this case, even the harmonic sum $\sum \frac 1n$ diverges. – lulu Oct 25 '20 at 10:38
  • Sorry, I edited the post, I am summing over X belonging to the domain {0,1} – ailauli69 Oct 25 '20 at 10:49
  • Sorry, do you just mean that the sum is over the two points $0$ and $1$? In that case, the answer is certainly $2$. I thought you meant that you were summing over the entire interval from $0$ to $1$. My mistake. – lulu Oct 25 '20 at 11:03

1 Answers1

1

If $|\{0, 1\}| = 2$ then the sum in the question equals 2. It is similar to $\sum_{k=1}^n 1 = n$.

DavidW
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