Staircases in .
Standard paths in another composition poset.
Statistics on Dyck paths.
Stirling distributions and Stirling numbers of the second kind. Computational problems in statistics
Stirling pairs
Strings with maximally many distinct subsequences and substrings.
Strong sequences and the weight of regular spaces
It will be shown that if in a family of sets there exists a strong sequence of the length then this family contains a subfamily consisting of pairwise disjoint sets. The method of strong sequences will be used for estimating the weight of regular spaces.
Strong sequences, binary families and Esenin-Volpin's theorem
One of the most important and well known theorem in the class of dyadic spaces is Esenin-Volpin's theorem of weight of dyadic spaces. The aim of this paper is to prove Esenin-Volpin's theorem in general form in class of thick spaces which possesses special subbases.
Struktur- und Anzahlformeln für Topologien auf endlichen Mengen.
Subsequence containment by involutions.
Substitutions, abstract number systems and the space filling property
In this paper we study multi-dimensional words generated by fixed points of substitutions by projecting the integer points on the corresponding broken halfline. We show for a large class of substitutions that the resulting word is the restriction of a linear function modulo and that it can be decided whether the resulting word is space filling or not. The proof uses lattices and the abstract number system associated with the substitution.
Substitutions on two letters, cutting segments and their projections
In this paper we study the structure of the projections of the finite cutting segments corresponding to unimodular substitutions over a two-letter alphabet. We show that such a projection is a block of letters if and only if the substitution is Sturmian. Applying the procedure of projecting the cutting segments corresponding to a Christoffel substitution twice results in the original substitution. This induces a duality on the set of Christoffel substitutions.
Succession rules and deco polyominoes
Succession rules and Deco polyominoes
In this paper, we examine the class of "deco" polyominoes and the succession rule describing their construction. These polyominoes are enumerated according to their directed height by factorial numbers. By changing some aspects of the "factorial" rule, we obtain some succession rules that describe various "deco" polyomino subclasses. By enumerating the subclasses according to their height and width, we find the following well-known numbers: Stirling numbers of the first and second kind,...
Suites infinies à répétitions bornées.
Sum relations for Lucas sequences.
Sums involving moments of reciprocals of binomial coefficients.
Sums involving the inverses of binomial coefficients.
Sums of Powered Characteristic Roots Count Distance-Independent Circular Sets
Significant values of a combinatorial count need not fit the recurrence for the count. Consequently, initial values of the count can much outnumber those for the recurrence. So is the case of the count, Gl(n), of distance-l independent sets on the cycle Cn, studied by Comtet for l ≥ 0 and n ≥ 1 [sic]. We prove that values of Gl(n) are nth power sums of the characteristic roots of the corresponding recurrence unless 2 ≤ n ≤ l. Lucas numbers L(n) are thus generalized since L(n) is the count in question...
Sums of reciprocals of the central binomial coefficients.