The expression you've written seems like a sum, but to be sure, I need to confirm your intent. If you are referring to the sum of the fractions:

$\frac{1}{3} + \frac{2}{3} + \cdots + \frac{1}{2025 \times 1013}$

It's essential to clarify whether this is a finite series with a defined pattern or if it's simply a sequence of terms. For now, I will interpret this as a sum of fractions with a general form. The sum could be related to harmonic series or other series with specific intervals. Could you confirm if you meant something like a sum of fractions of the form:

$\sum_{k=1}^{n} \frac{1}{3k} \quad \text{or similar?}$

Once you confirm, I will proceed with the appropriate steps to solve it.

If that is not what you meant, please clarify, and I will adjust my approach accordingly!

Would you like more detailed examples or clarification on a specific type of series?