Quant Researcher27 / 62
HardStochastic ProcessesAcceptance 45%
Expected Flips for HTH
Jane StreetSIG / Susquehanna
What is the expected number of fair-coin flips to first see the pattern H-T-H?
Approach
Set up states: ∅, H, HT, done.
Patterns that overlap themselves take longer on average.
Answer
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