This paper answers three open questions concerning the generative power of some simple variants of context-free grammars regulated by context conditions. Specifically, it discusses the generative power of so-called contextfree semi-conditional grammars (which are random context grammars where permitting and forbidding sets are replaced with permitting and forbidding strings) where permitting an...

We consider an extremal problem motivated by a paper of Balogh [J. Balogh, A remark on the number of edge colorings of graphs, European Journal of Combinatorics 27, 2006, 565–573], who considered edge-colorings of graphs avoiding fixed subgraphs with a prescribed coloring. More precisely, given r ≥ t ≥ 2, we look for n-vertex graphs that admit the maximum number of r-edge-colorings such that at...

This paper discusses the descriptional complexity of generalized forbidding grammars in context of degrees, numbers of nonterminals and conditional productions, and a new descriptional complexity measure—an index—of generalized forbidding grammars.

The purpose of this contribution1 is to set up a language to evaluate the results of concerted action among interdependent agents against predetermined properties that we can recognise as desirable from a deontic point of view. Unlike the standard view of logics to reason about coalitionally rational action, the capacity of a set of agents to take a rational decision will be restricted to what ...

Abstract This article explores the use of dharmaśāstra in Mughal India through case a little-known seventeenth-century Persian translation text entitled Aḥkām-i awāmir wa nawāhī-yi mazhab-i hunūd (Legal rulings on commanding [right] and forbidding [wrong] legal school Hindus). The work, apparently completed 1658 by Kāyastha named Lāl Bihārī Bhojpurī, is Yājñavalkya Smṛti together with Mitākṣarā...

We define classes of graphs based on forbidding and enforcing boundary conditions. Forbidding conditions prevent a graph to have certain combinations of subgraphs and enforcing conditions impose certain subgraph structures.We say that a class of graphs is an fe-class if the class can be defined through forbidding and enforcing conditions (fe-system). We investigate properties of fe-systems and ...

Inspired by biomolecular reactions and processes Rozenberg and Ehrenfeucht define forbidding and enforcing systems (fe-systems) on languages and study their language theoretical and computational properties (see [8–10, 41]). The general idea of the forbidding-enforcing paradigm is that a class of structures is defined by a pair of constraints, called an fe-system. In their model, an fe-system d...