Originally Posted by

**lambda** Hi,

I recently thought of the following problem and my basic grasp of probability and combinatorics is not enough to handle it:

**You flip a coin N times. What is the probability P(N,H) that you get at least one sequence of at least H heads in a row?**

Since this question deals with the number of times a result will happen, I tried to use a Poisson Distribution, but I'm having trouble separating the problem into mutually exclusive events.

I wrote a program to do a simulation and found that P(20,7) ≈ 0.058, so please make sure your answer fits with this result.

Thank you for your help!