The Kitāb al-Fuṣūl fī al-Ḥisāb al-Hindī (كتاب الفصول في الحساب الهندي), or The Book of Chapters on Hindu Arithmetic, authored by Abū al-Ḥasan Aḥmad ibn Ibrāhīm al-Uqlīdisī in 952 CE, is the earliest known Arabic treatise detailing Indian arithmetic and the use of Hindu-Arabic numerals. A unique manuscript of this work is preserved in the Yeni Cami Library in Istanbul. The treatise also offers the earliest documentation of numerals in use in Damascus and Baghdad.
Another significant reference is found in Talqīḥ al-Afkār bi-Rusūm Ḥurūf al-Ghubār (تلقيح الأفكار برُسوم حروف الغبار), or Fertilization of Thoughts with the Help of Dust Letters, by the Berber mathematician Ibn al-Yāsamīn (ابن الياسمين), who died in 1204. In the excerpt shown below, he presents the Indian numerals, stating:
“Know that specific forms have been chosen to represent all numbers; they are called ‘ghubār’ (dust), and they are these (first row). They may also appear like this (second row). However, among us, people use the first type of forms.”
An intriguing anecdote about Ibn al-Yāsamīn is that he composed mathematical poems, such as the Urjūza fī al-Jabr wa al-Muqābala, to make algebra more accessible. These poetic works were not only educational tools but also reflected the rich interplay between mathematics and literature in the Islamic Golden Age.
Champernowne’s constant, denoted as 0.123456789101112… , is formed by concatenating successive natural numbers. It can be represented as an infinite series. Concatenating 0. with prime numbers yields the Copeland–Erdős constant.
Photomosaic portrait of Albert Einstein made with random photographs of numbers. It is only when the viewer moves away from the image that the portrait of Einstein appears. It is the distance that creates and unveils the truth, because everything is relative, as Einstein once said, and everything depends on the context, the environment or the point of view.
Numbers 1 to 32 are placed along the circumference of a circle without repeating any number and still the sum of any two adjacent numbers in this circle is a perfect square!
Diaethria phlogea, the “89’98 butterfly”, is a species of butterfly of the Nymphalidae family found in Colombia, South America. The markings on its wing resemble a painted number: an 89, a 98 or even an 88.
Are there any other animals with numbers painted on their body?