The given sequence is:
$3, 9, 27, 81, \_\_\_\_\_, \_\_\_\_\_, \ldots$

This is a geometric sequence where each term is multiplied by 3 to get the next term.
Here’s how it works:

$9 = 3 \times 3$ $27 = 9 \times 3$ $81 = 27 \times 3$

Thus, the next term will be:

$81 \times 3 = 243$

And the term after that will be:

$243 \times 3 = 729$

So, the next terms in the sequence are 243 and 729.

Would you like more details or explanations? Here are some related questions:

1. What is the general formula for the nth term in a geometric sequence?
2. How do you differentiate between arithmetic and geometric sequences?
3. Can a sequence be neither arithmetic nor geometric?
4. What happens if a geometric sequence has a ratio less than 1?
5. How does the sum of an infinite geometric series work?

Tip: In a geometric sequence, always check the ratio between consecutive terms to identify the pattern!