Counting Nondecreasing Integer Sequences that Lie Below a Barrier
نویسندگان
چکیده
منابع مشابه
Counting Nondecreasing Integer Sequences that Lie Below a Barrier
Given a barrier 0 ≤ b0 ≤ b1 ≤ · · · , let f(n) be the number of nondecreasing integer sequences 0 ≤ a0 ≤ a1 ≤ · · · ≤ an for which aj ≤ bj for all 0 ≤ j ≤ n. Known formulæ for f(n) include an n × n determinant whose entries are binomial coefficients (Kreweras, 1965) and, in the special case of bj = rj + s, a short explicit formula (Proctor, 1988, p.320). A relatively easy bivariate recursion, d...
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ژورنال
عنوان ژورنال: The Electronic Journal of Combinatorics
سال: 2009
ISSN: 1077-8926
DOI: 10.37236/149