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I will explain question by example. I throw coin 100 times. What is the probability I get one or more series of 8 or more heads in a row? Which theorem should I use? Is there a equation for this kind of experiments? I tried looking towards to Bernoulli distribution but still no clue.
There are similar questions for little different problems:
This one is really close: 3 heads in a sequence when a fair coin is tossed 5 times but does not give theoretical explanation I am looking for.