Rational Number Expressible as Sum of Reciprocals of Distinct Squares/Mistake

Source Work

 * The Puzzles:
 * Egyptian Fractions
 * Egyptian Fractions

Mistake

 * The sum of the series $1 + 1 / 2^2 + 1 / 3^2 + 1 / 4^2 \ldots = \pi^2 / 6$, so the sum of different Egyptian fractions whose denominators are squares cannot exceed $\pi^2 / 6$, but might equal, for example, $\frac 1 2$.

Correction
It is implicit that $1$ is not included in the set of Egyptian fractions.

We have that:

Hence the sentence should end:
 * ... cannot exceed $\pi^2 / 6 - 1$, but might equal, for example, $\frac 1 2$.