What Swiss mathmeticion was responsible for instituting the use of the symbol for pi in mathematical notation?

{| ! colspan="2" | Leonhard Euler |}

{| ! Born | April 15, 1707(1707-04-15)

Basel, Switzerland ! Died | Sepember 18 [O.S. September 7] 1783

St Petersburg, Russia

! Residence | Prussia

Russia

Switzerland ! Nationality | Swiss ! Field | Mathematician and physicist ! Institutions | Imperial Russian Academy of Sciences

Berlin Academy ! Alma mater | University of Basel ! Academic advisor | Johann Bernoulli ! Notable students | Johann Hennert

Joseph Lagrange ! Known for | Euler's number ! Religious stance | Calvinist[1] ! Signature | Leonhard Paul Euler (pronounced IPA: [ˈœɪlɐ]; April 15, 1707 - September 18 [O.S. September 7] 1783) was a pioneering Swiss mathematician and physicist, who spent most of his life in Russia and Germany. Euler made important discoveries in fields as diverse as calculus and graph theory. He also introduced much of the modern mathematical terminology and notation, particularly for mathematical analysis, such as the notion of a mathematical function.[2] He is also renowned for his work in mechanics, optics, and astronomy. Euler is considered to be the preeminent mathematician of the 18th century and one of the greatest of all time. He is also one of the most prolific; his collected works fill 60-80 quarto volumes.[3] A statement attributed to Pierre-Simon Laplace expresses Euler's influence on mathematics: "Read Euler, read Euler, he is the master [i.e., teacher] of us all."[4] |}