An octagon is a closed shape formed by eight line segments, with an interior angle sum of 1080 degrees. It can be a regular octagon or an irregular octagon and is often used in architecture and signage design.
math system
'Bitwise method' usually refers to 'bitwise operation,' a low-level computational method that performs logical or shift operations on each binary digit of integers. It is not an independent 'number system' or 'numeral system' (the latter is often mistakenly called 'bitwise counting method').
Albert Einstein was one of the greatest physicists of the 20th century, proposing the theory of relativity and the mass-energy equivalence equation, and he won the 1921 Nobel Prize in Physics.
The Sieve of Eratosthenes is an ancient algorithm for quickly finding all prime numbers within a certain range, proposed by the Greek mathematician Eratosthenes.
Eratosthenes (circa 275–194 BC) was a famous Greek mathematician, astronomer, and geographer, born in Cyrene, Libya. His most celebrated achievement was pioneering a method for measuring the Earth's circumference, calculating a result with less than 5% error, and he was the first to propose the term 'geography,' earning him the title of 'Father of Geography' in later generations.
Arabic numerals are the ten digit symbols from 0 to 9 that we commonly use. Although called 'Arabic' numerals, they were actually invented by ancient Indians and later transmitted to Europe by Arabs, which is how they got this name. They are the number notation used worldwide today.
Φ is the twenty-first letter of the Greek alphabet, pronounced 'phi,' with an uppercase Φ and lowercase φ. The top left of the lowercase is usually open, and sometimes it is written as a smaller version of the uppercase shape. Besides being a letter, it represents various specialized meanings in different disciplines.
π is the fixed value obtained by dividing the circumference of a circle by its diameter; this ratio is the same for circles of any size. π is the symbol for the circle constant, representing the ratio of a circle's circumference to its diameter, approximately equal to 3.1415926535.
Any nonzero number raised to the power of 0 is equal to 1, while 0 raised to the power of 0 is meaningless. The formula is a^0 = 1 (a ≠ 0).