15, 31, 63, 127, 255, (….)

Question:
15, 31, 63, 127, 255, (….)

[A].

513

[B].

511

[C].

517

[D].

523

Answer: Option B

Explanation:

Each number is double the preceding one plus 1.

So, the next number is (255 x 2) + 1 = 511.