Coin pattern waiting times
Does heads–heads take longer than heads–tails?
Playback is compressed; model values are shown separately.
Make a prediction
Which pattern has the longer average wait?
Ready. Adjust the settings or press Run.
How it works & assumptions
For a fair independent coin, the expected first waiting time is 6 flips for HH and 4 for HT. Both patterns are checked on the same sequence.
A run stops after both patterns appear or at 200 flips. A capped run is unfinished, not a measured waiting time.
References: The Long Wait, Problem AB-3, The AMATYC Review 17 (1995–1996)
Random runs are reproducible from their setup links. Replay keeps the same seed; New random run changes it. A sample run need not equal the theoretical average.