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# initialMovieFragmentSequenceNumber

The sequence number of the initial movie fragment.

```
var initialMovieFragmentSequenceNumber: Int { get set }
```

## Discussion

If you combine movie fragments that you create from multiple asset writers, movie fragment sequence numbers need to increase monotonically across the entire combined collection, in temporal order. The default value of this property is `1`.

You can’t set this property after writing starts.

---

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