Down-step statistics in generalized Dyck pathsArticle
Authors: Andrei Asinowski ; Benjamin Hackl ; Sarah J. Selkirk
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Andrei Asinowski;Benjamin Hackl;Sarah J. Selkirk
The number of down-steps between pairs of up-steps in $k_t$-Dyck paths, a
generalization of Dyck paths consisting of steps $\{(1, k), (1, -1)\}$ such
that the path stays (weakly) above the line $y=-t$, is studied. Results are
proved bijectively and by means of generating functions, and lead to several
interesting identities as well as links to other combinatorial structures. In
particular, there is a connection between $k_t$-Dyck paths and perforation
patterns for punctured convolutional codes (binary matrices) used in coding
theory. Surprisingly, upon restriction to usual Dyck paths this yields a new
combinatorial interpretation of Catalan numbers.