Many functions in combinatorics follow simple recursive relations of the type F(n,k) = a(n-1, k)F(n-1,k)+b(n-1,) Fk-1(n-1,k-1). Treating such functions as (infinite) triangular matrices and calling a(n,k) and b(n,k) g...
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Many functions in combinatorics follow simple recursive relations of the type F(n,k) = a(n-1, k)F(n-1,k)+b(n-1,) Fk-1(n-1,k-1). Treating such functions as (infinite) triangular matrices and calling a(n,k) and b(n,k) generators of F, our paper will study the following question: Given two triangular arrays and their generators, how can we give explicit formulas for the generators of the product matrix? Our results can be applied to factor infinite matrices with specific types of generators (e.g. a(n,k) =a(n)' +a(k)(")) into matrices with 'simpler' types of generators. These factorization results then can be used to give construction methods for inverse matrices (yielding conditions for self-inverse matrices), and results for convolutions of recursively defined functions. Slightly extending the basic techniques, we will even be able to deal with certain cases of nontriangular infinite matrices. As a side-effect, many seemingly separate results about recursive combinatorial. functions will be shown to be special cases of the general framework developed here. (C) 2001 Elsevier Science B.V. All rights reserved.
This paper is divided in two parts: in Section 2, we define recursively a privileged basis of the primitive forms in a symplectic space(V^(2n), ω). Successively, in Section 3, we apply our construction in the se...
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This paper is divided in two parts: in Section 2, we define recursively a privileged basis of the primitive forms in a symplectic space(V^(2n), ω). Successively, in Section 3, we apply our construction in the setting of Heisenberg groups H^n, n ≥ 1, to write in coordinates the exterior differential of the so-called Rumin's complex of differential forms in H^n.
We study M (n), the number of distinct values taken by multinomial coefficients with upper entry n, and some closely related sequences. We show that both p(P)(n)/M(n) and M(n)/p(n) tend to zero as n goes to infinity, ...
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We study M (n), the number of distinct values taken by multinomial coefficients with upper entry n, and some closely related sequences. We show that both p(P)(n)/M(n) and M(n)/p(n) tend to zero as n goes to infinity, where p(P)(n) is the number of partitions of n into primes and p(n) is the total number of partitions of n. To use methods from commutative algebra, we encode partitions and multinomial coefficients as monomials. (C) 2005 Elsevier Inc. All rights reserved.
Two interrelated, finite difference and graph theoretic, approaches to trigonometry are developed by combining a generalization of the finite difference method first employed by Viete, with solution techniques, based ...
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Two interrelated, finite difference and graph theoretic, approaches to trigonometry are developed by combining a generalization of the finite difference method first employed by Viete, with solution techniques, based on signal flow graphs, for finite difference equations with variable coefficients, and a scaling approach to trigonometry, based on the polygonometric identities.
A Factorial Pulse Coding approach using combinatorial functions for coding of pulse sequences is presented. An arithmetic coding approach for coding of pulse sequences is also described. Factorial pulse coding and ari...
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ISBN:
(纸本)9781424471379
A Factorial Pulse Coding approach using combinatorial functions for coding of pulse sequences is presented. An arithmetic coding approach for coding of pulse sequences is also described. Factorial pulse coding and arithmetic coding are compared. A method of combining the two approaches is proposed. The proposed combining method works by extending the pulse sequence by one bit whose probability is found from the arithmetic coding bounds.
Let the Fleck numbers, C-n(t, q), be defined such that C-n(t, q) = Sigma(k equivalent to q(mod n)) (-1)(k)((t)(k)) For prime p, Fleck obtained the result C-p(t, q) equivalent to 0(mod p(((Left perpendicular)/(t-1)/(p-...
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Let the Fleck numbers, C-n(t, q), be defined such that C-n(t, q) = Sigma(k equivalent to q(mod n)) (-1)(k)((t)(k)) For prime p, Fleck obtained the result C-p(t, q) equivalent to 0(mod p(((Left perpendicular)/(t-1)/(p-1)(right perpendicular)))), where (Left perpendicular).(right perpendicular) denotes the usual floor function. This congruence was extended 64 years later by Weisman, in 1977, to include the case n = p(alpha) In this paper we show that the Fleck numbers occur naturally when one considers a symmetric n x n matrix, M, and its inverse under matrix multiplication. More specifically, we take M to be a symmetrically constructed n x n associated magic square of odd order, and then consider the reduced coefficients of the linear expansions of the entries of M-t with t is an element of Z. We also show that for any odd integer, n = 2m + 1, n >= 3, there exist geometric polynomials in m that are linked to the Fleck numbers via matrix algebra and p-adic interaction. These polynomials generate numbers that obey a reciprocal type of congruence to the one discovered by Fleck. As a by-product of our investigations we observe a new identity between values of the Zeta functions at even integers. Namely zeta(2j) = (-1)(j+1) (j pi(2)j/(2j + 1)! + Sigma(j=i)(k=1) (-1)(k)pi(2j-2k)/(2j - 2k + 1)! zeta(2k)) We conclude with examples of combinatorial congruences, Vandermonde type determinants and Number Walls that further highlight the symmetric relations that exist between the Fleck numbers and the geometric polynomials.
A special case of the problem discussed in this paper occurs in connection with non-parametric classification and is introduced from this point of view. The special case concerns the computation of expectations of sta...
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A special case of the problem discussed in this paper occurs in connection with non-parametric classification and is introduced from this point of view. The special case concerns the computation of expectations of statistical functions of the “distance” between pairs of fixed-length sequences over a binary alphabet with given a priori state transition probabilities. The general problem involves an extension to alphabets of arbitrary order and the comparison of an arbitrary number of fixed-length sequences. Given a set of sequences, it is shown that for a large class of functions exact computation may be carried out by an algorithm whose computation time is independent of the length of the sequences. It is further shown that results for all functions of this class may be derived from a small number of basis functions. Two methods for computing basis functions are given. Basis functions for the commonly encountered special case involving pairs of binary sequences are given explicitly.
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