Enumeration of alternating sequences
نویسندگان
چکیده
منابع مشابه
Enumeration of snakes and cycle-alternating permutations
Springer numbers are analogs of Euler numbers for the group of signed permutations. Arnol’d showed that they count some objects called snakes, which generalize alternating permutations. Hoffman established a link between Springer numbers, snakes, and some polynomials related with the successive derivatives of trigonometric functions. The goal of this article is to give further combinatorial pro...
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ژورنال
عنوان ژورنال: Discrete Mathematics
سال: 1977
ISSN: 0012-365X
DOI: 10.1016/0012-365x(77)90060-7