Plan of the course <b>Combinatorial Counting</b> in summer term 2025/26
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The symbolic method, Catalan numbers and Polya's theorem
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Numbers of SAWs in the hexagonal grid
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Some results from the book A. Barvinok - Combinatorics and Complexity of
Partition Functions
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<a href="COMCOU_LN26.pdf">lecture notes</a> (preliminary, updated February 27, 2026)
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Lecture 1, February 20, 2026.
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A derivation of the formula for the Catalan numbers C_n.
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Lecture 2, February 27, 2026.
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What is (1 - 4x)^{1/2}?
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Lecture 3, March 6, 2026.
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Four proofs that (C_n) is not a linear recurrence sequence.
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