Ludolph van Ceulen (28 January 1540 – 31 December 1610) was a German mathematician. Born in Hildesheim, Germany. Like many Germans during the Catholic Inquisitions, he emigrated to the Netherlands. January 28 is the 28th day of the year in the Gregorian calendar. ... Year 1540 was a leap year starting on Thursday (link will display the full calendar) of the Julian calendar. ... December 31 is the 365th day of the year (366th in leap years) in the Gregorian calendar. ... // Events January 7 - Galileo Galilei discovers the Galilean moons of Jupiter. ... Leonhard Euler, one of the greatest mathematicians of all time A mathematician is a person whose primary area of study and research is the field of mathematics. ... â–¶ (help· info) is a city in Lower Saxony, Germany. ... Inquisition (capitalized I) is broadly used, to refer to things related to judgment of heresy by the Roman Catholic Church. ...

He moved to Delft to teach fencing and mathematics. In 1594 he opened a fencing school in Leiden. In 1600 he was appointed the first professor of mathematics at the University of Leiden. He died in Leiden. Country Netherlands Province South Holland Coordinates Area 24. ... Fencing advertisement for the 1900 Summer Olympic Games This article is about the sport, which is distinguished from stage fencing and academic fencing (mensur). ... Euclid, Greek mathematician, 3rd century BC, as imagined by by Raphael in this detail from The School of Athens. ... Events February 27 - Henry IV is crowned King of France at Rheims. ... Leyden redirects here. ... 1600 was a leap year starting on Saturday of the Gregorian calendar (or a leap year starting on Tuesday of the 10-day slower Julian calendar). ... Leiden University in the city of Leiden, is the oldest university in the Netherlands. ...

Calculating π

Ludolph van Ceulen spent a major part of his life calculating the numerical value of the mathematical constant π, using essentially the same methods as those employed by Archimedes some two thousand years earlier. He published a 20-decimal value in his 1596 book Van den Circkel ("On the Circle"), later expanding this to 35 decimals. After his death, the "Ludolphine number", When a circles diameter is 1, its circumference is Ï€. The mathematical constant Ï€ is an irrational real number, approximately equal to 3. ... Archimedes (Greek: c. ... When a circles diameter is 1, its circumference is Ï€. The mathematical constant Ï€ is an irrational real number, approximately equal to 3. ...

3.14159265358979323846264338327950288...,

was engraved on his tombstone in Leiden. The tombstone was later lost but was restored in 2000. Headstones in the Japanese Cemetry in Broome, Western Australia A cemetery in rural Spain A typical late 20th century headstone in the United States A headstone, tombstone or gravestone is a marker, normally carved from stone, placed over or next to the site of a burial. ... 2000 (MM) was a leap year starting on Saturday of the Gregorian calendar. ...

External links

• Oomes, R. M. Th. E.; Tersteeg, J. J. T. M.; Top, J. "The epitaph of Ludolph van Ceulen." Nieuw Arch. Wiskd. (5) 1 (2000), no. 2. online in Dutch.
• MacTutor biography of van Ceulen