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Formal map

Ook! Expert · Lesson 9

Formal map

Bijection proof sketch.

Lessons · Ook! Expert · Lesson 9 of 10

Formal map

Bijection proof sketch.

Illustration for the Ook! course — Bijection proof sketch.

The rest of the course

Lesson 1 is on the house.

The rest of this course opens with the paper (A$5 a month), the Daily (free forever — email), or a Lessons donate — pay what you can. A$5 or more includes a month of the Reader desk.

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Lesson 8 Lesson 10

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Formal map · Ook! Expert — The Gold Standard