Observe the differences between consecutive terms:
\[
6 - 3 = 3, \quad 11 - 6 = 5, \quad 18 - 11 = 7, \quad 27 - 18 = 9
\]
The differences between consecutive numbers are increasing by 2 each time: 3, 5, 7, 9... Hence, the next difference should be 11.
Therefore, the next term is:
\[
27 + 11 = 36
\]
Answer: \(\boxed{36}\)