Royal cypher Royal cypher In modern heraldry, a royal cypher is a monogram-like device of a country's reigning sovereign, typically consisting of the initials of the monarch's name and title, sometimes interwoven and often surmounted by a crown. Where such a cypher is used by an emperor or empress, it is called an "imperial cypher". In the system used by various Commonwealth realms, the title is abbreviated as "R" for "rex" or "regina" (Latin for "king" and "queen"). Previously, "I" stood for "imperator" or "imperatrix" (Latin words for "emperor" and "empress") of India. The cypher is displayed on some government buildings, impressed
Formal system of inference rules are decidable sets or semidecidable sets, respectively. The entailment of the system by its logical foundation is what distinguishes a formal system from others which may have some basis in an abstract model. Often the formal system will be the basis for or even identified with a larger theory or field (e.g. Euclidean geometry) consistent with the usage in modern mathematics such as model theory. A formal language is a language that is defined by a formal system. Like languages in linguistics, formal languages generally have two aspects: In computer science and linguistics a formal grammar is