The following screenshot is taken from some lecture notes on actuarial mathematics:

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[![notes](https://i.stack.imgur.com/1yA0R.png)](https://i.stack.imgur.com/1yA0R.png)

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As you can see, the notation $h \ll 1$ is used here (in the first line of the proof).

Does anyone know what this is supposed to denote? I first suspected that it was a typo and was instead supposed to be $h < 1$ or $h \leq 1$, but the same notation is used on several occasions (leading me to believe that its use must be intentional).