houghtonlib: “For the sake of brevity we will write this number as π; thus π is equal to
houghtonlib: “For the sake of brevity we will write this number as π; thus π is equal to half the circumference of a circle of radius 1.” Euler, Leonhard, 1707-1783. Introductio in analysin infinitorum, 1748. *GC7 Eu536 748i Houghton Library, Harvard University -- source link
#pi day#18th century