Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.3 4.3bsd-beta 6/6/85; site ucbvax.BERKELEY.EDU Path: utzoo!watmath!clyde!cbosgd!hplabs!ucbvax!brahms!weemba From: weemba@brahms.BERKELEY.EDU (Matthew P. Wiener) Newsgroups: net.math Subject: The Null-Graph Message-ID: <12788@ucbvax.BERKELEY.EDU> Date: Sat, 29-Mar-86 13:23:49 EST Article-I.D.: ucbvax.12788 Posted: Sat Mar 29 13:23:49 1986 Date-Received: Sun, 30-Mar-86 10:45:15 EST Sender: usenet@ucbvax.BERKELEY.EDU Reply-To: weemba@brahms.BERKELEY.EDU (Matthew P. Wiener) Organization: University of California, Berkeley Lines: 38 I don't remember the reference for this paper by F Harary and R C Read except that it was in a Springer Lecture Notes. The paper, while humorous, is serious. I excerpt here from the beginning of their paper. IS THE NULL-GRAPH A POINTLESS CONCEPT? ABSTRACT The graph with no points and no lines is discussed critically. Arguments for and against its official admittance as a graph are presented. This is accompanied by an extensive survey of the literature. Paradoxical properties of the null-graph are noted. No conclusion is reached. 1. INTRODUCTION ... Some writers in graph theory ... have introduced to concept of a (or the) "null-graph"--having no points and no lines; see Figure 1. ... Note that it is not a question of whether the null-graph "really exists"; it is simply a question of whether there is any point in it. Figure 1. ucbvax!brahms!weemba Matthew P Wiener/UCB Math Dept/Berkeley CA 94720