en.wikipedia.org/wiki/John_Wallis

John Wallis was an English mathematician who is given partial credit for the development of infinitesimal calculus. Between 1643 and 1689 he served as chief cryptographer for Parliament and, later, the royal court. He is credited with introducing the symbol ∞ for infinity. .... He stated, but did not prove, the corresponding result for a curve of the form y ...

www.emma.cam.ac.uk/about/history/famous/?id=7

Mathematician who developed calculus and who introduced the symbol for ' infinity', ∞. John Wallis, 'the greatest of Newton's precursors in mathematics', did not ...

www.britannica.com/biography/John-Wallis

Wallis' appointment in 1649 as Savilian professor of geometry at the ... thus he did not follow Cavalieri's geometric approach and instead assigned numerical values to spatial indivisibles. ... He invented and introduced the symbol ∞ for infinity.

mathcentral.uregina.ca/qq/database/qq.09.98/kelly1.html

Does it have a name? ... (Infinity is in the calculus section.) ... Cajori says that the infinity symbol was introduced by John Wallis (1616-1703) in 1655 in his De ...

www.newworldencyclopedia.org/entry/John_Wallis

Oct 5, 2011 ... Christopher Wren, the great English architect and Wallis' colleague in ... He states, but does not prove, the corresponding result for a curve of the form y = xp/ q. .... He also introduced the symbol for infinity, ∞, which is still used ...

www.maths.tcd.ie/pub/HistMath/People/Wallis/RouseBall/RB_Wallis.html

They are notable partly for the introduction of the use of infinite series as an ... work did something to make the method intelligible to all mathematicians: it is the ...

www.encyclopedia.com/people/science-and-technology/mathematics-biographies/john-wallis

Here he also first introduced the sign for infinity and used 1/∞ to represent, ... one —at a time when the symbolism of analysis had not yet been properly developed. ... as Wallis himself emphasized and partly because it did not suit the taste of ...

hsm.stackexchange.com/questions/3814/where-did-john-wallis-get-the-idea-for-infty

May 21, 2016 ... Infinity. The ∞ symbol was introduced by John Wallis (1616-1703) in ... he derived ∞ [the infinity symbol] from the old Roman sign for 1,000, ...

mathforum.org/library/drmath/view/59141.html

What is the name for the infinity symbol (the on-its-side figure eight)? ... [infinity] to signify infinite number was introduced by John Wallis in 1655 ...