To simplify the expression \( 13^{-5} \times 13^{-11} \), we can use the properties of exponents. Specifically, we utilize the rule that states \( a^m \times a^n = a^{m+n} \).
So we add the exponents:
\[ 13^{-5} \times 13^{-11} = 13^{-5 + (-11)} = 13^{-16} \]
Now we want to express this with only positive exponents.
To convert \( 13^{-16} \) to a positive exponent, we use the property \( a^{-m} = \frac{1}{a^m} \):
\[ 13^{-16} = \frac{1}{13^{16}} \]
Looking at the options provided:
- \( \frac{1}{26^6} \)
- \( \frac{1}{13^6} \)
- \( \frac{1}{26^{16}} \)
- \( \frac{1}{13^{16}} \)
The equivalent expression is:
\(\frac{1}{13^{16}}\)
Thus, the answer is:
\(\boxed{\frac{1}{13^{16}}}\)