A new aperiodic tile set containing only 13 tiles over 5 colors is presented. Its construction is based on a technique recently developed by J. Kari. The tilings simulate behavior of sequential machines that multiply real numbers in balanced representations by real constants.
The problem: How to convince programmers and computer science students that the proving of correctness of their programs is a way of program verification, which is feasible to anybody who has some experience with systematic thinking and reasoning (represented by some mathematical or engineering training)? The question: Why even good programmers and good… (More)
Program execution is not adequately reflected in usual syntactic programming language definition by formal grammar, although either actual or mental execution is referred to during reading (tracing) and correctness proving. An advanced programming languages definition associates in input/output variables, the domain, and the computable function with each… (More)
Informal mathematical proofs admit and require interpretation while formal logic proofs suppress (abstract from) meanings. The former is closely related to problem solving and computer programming. The latter, which is commonly used for proving program correctness, complicates this procedure because it separates problem solving from programming. A… (More)
The parallelity means "simultaneous performance or execution" and it may concern either computer units of different sorts (e.g. a memory and a processor), or computer units of the same sort (e.g. several processors).The computers Illiac 4 and Burroughs Scientific Processor (BSP) (announced recently) have several arithmetic processors. They are designed for… (More)