Fun fact: 23 out of the 42 Dyck paths (start & end on axis, upstep (1, 1), downstep (1, -1)) of length 10 have a unique peak. 🧐🧪 The sequence counting them w.r.t. their length starts as 1, 1, 3, 8, 23, 71, 229, 759, 2566, ... (meaning there are, e.g., 2566 many of length 18). OEIS: oeis.org/A152880

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