Binary Quote

$a+b$ must be a count of the total number of digits that occur.

Since the sentence already has two, maybe the answer is three? No. Three needs two digits ( $11$ ) so that's not big enough.

Ok, how about four? No. Four needs three digits ( $100$ ) so the total is now five.

Will five work? Yes! $\boxed{101}$ brings the digit total to five.

There can't be six digits or more in total because the value of the number surpasses the number of digits. A sixth digit requires a four-digit number, but $1000$ is sixteen -- way too big.

There are $2$ 0's and $3$ 1's in this sentence, then $2 + 3 = 101$ .

But you should precise that $a$ and $b$ are both different of $1$ because there is another possible answer :

There are $1$ 0's and $6$ 1's in this sentence, then $1 + 6 = 111$ .