Knaph

Natural numbers

The counting numbers 1, 2, 3, ... - what you get by starting at one and repeatedly adding one more.

Level 1 · Foundation

You can count, compare and add with natural numbers, and know they never run out.

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Levels of understanding

  1. 1

    Foundation

    You can count, compare and add with natural numbers, and know they never run out.

  2. 2

    Deeper

    You see the naturals as a discrete skeleton sitting inside the continuous real line - and why that difference matters.

    Master level 1 first

    Real numbersOnly once you know the reals can you see what makes the naturals special - they are isolated points with gaps between them, while the reals have none.

Builds on

Nothing — you can start here.

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