ALGORITMA PEMBANGKITAN MENGGUNAKAN POHON

Pembangkitan secara lengkap objek-objek dari kelas kombinatorial tertentu adalah mencari cara atau metode atau algoritma untuk mencacah (list, enumerate) semua objek dalam urutan tertentu tanpa pengulangan dan tidak melewatkan satu objek pun. Salah satu pendekatan dalam membangkitkan objek kombinatorial secara lengkap adalah dengan pohon pembangkit. Pohon pembangkit adalah suatu sistem yang mempunyai akar dan cabang-cabangnya yang dapat direpresentasikan dalam aturan yang dikenal dengan nama aturan suksesi. Pendekatan ini banyak digunakan karena dengan aturan suksesi dapat diterjemahkan kedalam bentuk-bentuk lain seperti operator linier pada polinomial dengan satu variabel, perkalian matriks, atau kode tertentu seperti kode Gray. Dari pohon pembangkit dapat pula dimungkinkan suatu algoritma pembangkitan acak. Makalah membahas pohon pembangkit dan aplikasinya pada objek kombinatorial untai Fibonacci, permutasi dan permutasi dengan siklus

Pembangkitan Permutation dengan Siklus

Makalah ini membahas pembangkitan lengkap objek kombinatorial permutasi khususnya permutasi n dengan satu siklus dengan panjang n. Metode yang akan digunakan dalam pembangkitan permutasi dengan memperhatikan siklus tersebut menggunakan pendekata

PEMBM GKITAl"l PERMUTATION DENGAN SIKLUS

Makalah ini membahas pembangkitan leng\c:ap objek kombinatorial pennutasi khususnya pennutasi n dengan satu siklus dengan panjang n. Metode yang akan digunakan dalam pembangkitan pennutasi dengan memperharikan siklus tersebut menggunakan pendekatan pohon pembangkit atau metode ECO (enumerating combinatorial objects). Dalam metode ini setiap objek diperoleh dati objek yang lebih kecil dengan melakukan ekspansi lokal, Seringkali ekspansi lokal tersebut sangat teratur dan dapat dijelaskan dalamamran suksesi, Metode ECO ini telah ditunjukkan efektif untuk beberapa struktur kombinatorik. Efekrif dalam pembangkitan kombinatorik berarti: waktu untuk menghasilkan (running rime) sebanding dengan banyaknya objek yang dihasilkan, yang merupakan syarat penring dalam merancang algoritma pembangkitan obiek kombinatorial

Note on Ward-Horadam H(x) - binomials' recurrences and related interpretations, II

We deliver here second new $\textit{H(x)}-binomials'$ recurrence formula, were $H(x)-binomials'$ array is appointed by $Ward-Horadam$ sequence of functions which in predominantly considered cases where chosen to be polynomials . Secondly, we supply a review of selected related combinatorial interpretations of generalized binomial coefficients. We then propose also a kind of transfer of interpretation of $p,q-binomial$ coefficients onto $q-binomial$ coefficients interpretations thus bringing us back to $Gy{\"{o}}rgy P\'olya$ and Donald Ervin Knuth relevant investigation decades ago.Comment: 57 pages, 8 figure

Enumeration of polyominoes defined in terms of pattern avoidance or convexity constraints

In this thesis, we consider the problem of characterizing and enumerating sets of polyominoes described in terms of some constraints, defined either by convexity or by pattern containment. We are interested in a well known subclass of convex polyominoes, the k-convex polyominoes for which the enumeration according to the semi-perimeter is known only for k=1,2. We obtain, from a recursive decomposition, the generating function of the class of k-convex parallelogram polyominoes, which turns out to be rational. Noting that this generating function can be expressed in terms of the Fibonacci polynomials, we describe a bijection between the class of k-parallelogram polyominoes and the class of planted planar trees having height less than k+3. In the second part of the thesis we examine the notion of pattern avoidance, which has been extensively studied for permutations. We introduce the concept of pattern avoidance in the context of matrices, more precisely permutation matrices and polyomino matrices. We present definitions analogous to those given for permutations and in particular we define polyomino classes, i.e. sets downward closed with respect to the containment relation. So, the study of the old and new properties of the redefined sets of objects has not only become interesting, but it has also suggested the study of the associated poset. In both approaches our results can be used to treat open problems related to polyominoes as well as other combinatorial objects.Comment: PhD thesi

Enumeration of convex polyominoes using the ECO method

International audienceECO is a method for the enumeration of classes of combinatorial objects based on recursive constructions of such classes. In the first part of this paper we present a construction for the class of convex polyominoes based on the ECO method. Then we translate this construction into a succession rule. The final goal of the paper is to determine the generating function of convex polyominoes according to the semi-perimeter, and it is achieved by applying an idea introduced in [11]

Enumeration of convex polyominoes using the ECO method

ECO is a method for the enumeration of classes of combinatorial objects based on recursive constructions of such classes. In the first part of this paper we present a construction for the class of convex polyominoes based on the ECO method. Then we translate this construction into a succession rule. The final goal of the paper is to determine the generating function of convex polyominoes according to the semi-perimeter, and it is achieved by applying an idea introduced in [11]

Enumeration of convex polyominoes using the ECO method

ECO is a method for the enumeration of classes of combinatorial objects based on recursive constructions of such classes. In the first part of this paper we present a construction for the class of convex polyominoes based on the ECO method. Then we translate this construction into a succession rule. The final goal of the paper is to determine the generating function of convex polyominoes according to the semi-perimeter, and it is achieved by applying an idea introduced in [11]