These are my self-made contributions:

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  Isola Tiberina
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  Pistachios
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  The behaviour of the Arnold's cat map
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  Venn diagram of A→B
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  Sir Isaac Newton
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  A Collatz sequence
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  Dominos
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  Affinization of a projective plane
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  2D representation of Brouwer fixed point theorem
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  1D representation of Brouwer fixed point theorem
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  Graph of ${\displaystyle f(x)=sin(1/x)}$
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  Definition of the winding number
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  Illustration of a property of the tangent to an ellipse
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  An example of a vector field
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  A torus
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  Stating Heros' theorem
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  Proving the Hero's theorem
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  Sperner's lemma in 1D
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  Sperner's lemma in 2D
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  Proving Sperner's lemma
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  Proving Brouwer's theorem via Sperner's lemma
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  Illustration of the Index theorem
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  Stable and unstable equilibria
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  Index of a vector field
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  Proving the fundamental theorem of algebra