TAILIEUCHUNG - Báo cáo toán học: " FRUIT SALAD"

Tuyển tập các báo cáo nghiên cứu khoa học ngành toán học tạp chí toán học quốc tế đề tài: FRUIT SALAD. | FRUIT SALAD András Gyarfas Computer and Automation Institute Hungarian Academy of Sciences Gyarfas@ Abstract. Paul Erdos liked fruit salad. I mixed this one for him from ingredients obtained while working on some of his problems. He was pleased by it and carried it to several places to offer to others as well. It is very sad that I have to add to the manuscript dedicated to his memory. 1. Nearly bipartite graphs. Szentendre 1994. Although we are in the shade the summer afternoon is very hot the water Paul poured on the warm tiles of the terrace does not give too much relief. After reciting famous lines of a classical Hungarian poet slightly rewritten by changing life to theorem Paul feels it is time to read from his problem book. This has nothing to do with the BOOK to which even he had no free access. Soon he reads something immediately awakening my senses numbed by the humidity. A problem of Hajnal and myself assume that G is a graph in which every subset S of vertices spans a subgraph with at least b VJ - k independent vertices. Then with some suitable function f one can remove f k vertices from G so that the remaining graph is bipartite. It is useful to look at special cases in the process of becoming familiar with a problem. That is precisely what I am doing now nearly two years after hearing the problem from Paul. I am looking and working without success at the case k 0. Then we have a graph in which every subset of 2t vertices spans a subgraph with at least t independent vertices the condition for the odd subsets follows from this . For easier reference call these graphs nearly bipartite. The problem is whether nearly bipartite graphs become bipartite after the deletion of a constant number of vertices to justify the terminology . There is an example showing that the following conjecture if true is best possible. 1 THE ELECTRONIC JOURNAL OF COMBINATORICS 4 1997 R8 2 Conjecture 1. Nearly bipartite graphs can be made bipartite by the .

• Báo cáo khoa học
• tài liệu báo cáo nghiện cứu khoa học
• cách trình bày báo cáo
• kiến thức toán học
• báo cáo toán học
• các bài toán hay
• trình bày báo cáo
• báo cáo ngành văn học
• báo cáo tiếng anh
• nghiên cứu văn thơ
• giọng điệu trào phúng
• nghiên cứu khoa học
• báo cáo khoa học
• thơ lục bát
• chính sách phát triển
• gia đình việt nam
• nghiên cứu xã hội