The starting point of this paper is a collection of properties of an algorithm that have been distilled from the informal descriptions of what an algorithm is that are given in standard works from the mathematical and computer science literature. Based on that, the notion of a proto-algorithm is introduced. The thought is that algorithms are equivalence classes of proto-algorithms under some equivalence relation. Three equivalence relations are defined. Two of them give bounds between which an appropriate equivalence relation must lie. The third lies in between these two and is likely an appropriate equivalence relation. A sound method is presented to prove, using an imperative process algebra based on ACP, that this equivalence relation holds between two proto-algorithms.

翻译：本文的出发点是从数学和计算机科学文献中关于算法非形式化描述的标准著作中提炼出的算法属性集合。基于此，本文引入了原始算法的概念。其核心思想是：算法是在某种等价关系下原始算法的等价类。本文定义了三种等价关系，其中两种界定了合适等价关系的范围边界，第三种则介于两者之间，可能是恰当的等价关系。最后提出了一种基于ACP指令进程代数的可靠方法，用于证明该等价关系在两个原始算法之间成立。