Number Sequence Pattern: 13, 27, 57, 119, 245, ...

The next number in the sequence is 503.

To find the next number, we can observe that each number is obtained by multiplying the previous number by 2 and adding 1.

13 * 2 + 1 = 27 27 * 2 + 1 = 57 57 * 2 + 1 = 119 119 * 2 + 1 = 245

Therefore, 245 * 2 + 1 = 503.