The Lahun Mathematical Papyri (also known as the Kahun Mathematical Papyri) is an ancient Egyptian mathematical text. It forms part of the Kahun Papyri, which was discovered at El-Lahun (also known as Lahun, Kahun or Il-Lahun) by Flinders Petrie during excavations of a workers' town near the pyramid of the Twelfth Dynasty pharaoh Sesostris II. The Kahun Papyri are a collection of texts including administrative texts, medical texts, veterinarian texts and six fragments devoted to mathematics.
Fragments
The mathematical texts most commented on are usually named:
- Lahun IV.2 (or Kahun IV.2) (UC 32159): This fragment contains a table of Egyptian fraction representations of numbers of the form 2/n. A more complete version of this table of fractions is given in the Rhind Mathematical Papyrus.
- Lahun IV.3 (or Kahun IV.3) (UC 32160) contains numbers in arithmetical progression and a problem very much like problem 40 of the Rhind Mathematical Papyrus. Another problem on this fragment computes the volume of a cylindrical granary. In this problem the scribe uses a formula which takes measurements in cubits and computes the volume and expresses it in terms of the unit khar. Given the diameter (d) and height (h) of the cylindrical granary:
- .
- In modern mathematical notation this is equal to
- (measured in khar).
- This problem resembles problem 42 of the Rhind Mathematical Papyrus. The formula is equivalent to measured in cubic-cubits as used in the other problems.
- Lahun XLV.1 (or Kahun XLV.1) (UC 32161) contains a group of very large numbers (hundreds of thousands).
- Lahun LV.3 (or Kahun LV.3) (UC 32134A and UC 32134B) contains a so-called aha problem which asks one to solve for a certain quantity. The problem resembles ones from the Rhind Mathematical Papyrus (problems 24–29).
- Lahun LV.4 (or Kahun LV.4) (UC 32162) contains what seems to be an area computation and a problem concerning the value of ducks, geese and cranes. The problem concerning fowl is a baku problem and most closely resembles problem 69 in the Rhind Mathematical Papyrus and problems 11 and 21 in the Moscow Mathematical Papyrus.
- Unnamed fragment (UC 32118B). This is a fragmentary piece.
2/n tables
The Lahun papyrus IV.2 reports a 2/n table for odd n, n = 1, ..., 21. The Rhind Mathematical Papyrus reports an odd n table up to 101. These fraction tables were related to multiplication problems and the use of unit fractions, namely n/p scaled by LCM m to mn/mp. With the exception of 2/3, all fractions were represented as sums of unit fractions (i.e. of the form 1/n), first in red numbers. Multiplication algorithms and scaling factors involved repeated doubling of numbers, and other operations. Doubling a unit fraction with an even denominator was simple, dividing the denominator by 2. Doubling a fraction with an odd denominator however results in a fraction of the form 2/n. The RMP 2/n table and RMP 36 rules allowed scribes to find decompositions of 2/n into unit fractions for specific needs, most often to solve otherwise un-scalable rational numbers (i.e. 28/97 in RMP 31, and 30/53 n RMP 36 by substituting 26/97 + 2/97 and 28/53 + 2/53) and generally n/p by (n − 2)/p + 2/p. Decompositions were unique. Red auxiliary numbers selected divisors of denominators mp that best summed to numerator mn.
See also
References
- The Lahun Papyri at University College London
- "Lahun Papyri: table texts". Retrieved 15 August 2016.
- ^ Clagett, Marshall Ancient Egyptian Science, A Source Book. Volume Three: Ancient Egyptian Mathematics (Memoirs of the American Philosophical Society) American Philosophical Society. 1999 ISBN 978-0-87169-232-0; Annette Imhausen, Jim Ritter: Mathematical Fragments, In: Marc Collier, Stephen Quirke: The UCL Lahun Papyri: Religious, Literary, Legal, Mathematical and Medical, Oxford 2004, ISBN 1-84171-572-7, 92-93
- "Lahun Papyri: table texts". Retrieved 15 August 2016.
- Annette Imhausen, Jim Ritter: Mathematical Fragments, In: Marc Collier, Stephen Quirke: The UCL Lahun Papyri: Religious, Literary, Legal, Mathematical and Medical, Oxford 2004, ISBN 1-84171-572-7, 84–85
- Legon, J., A Kahun mathematical fragment, retrieved from Archived 3 September 2012 at archive.today, based on Discussions in Egyptology 24 (1992), p. 21–24
- Gay Robins and Charles Shute, The Rhind Mathematical Papyrus, British Museum Press, Dover Reprint, 1987.
- Katz, Victor J. (editor), Imhausen, Annette et al. The Mathematics of Egypt, Mesopotamia, China, India, and Islam: A Sourcebook, Princeton University Press. 2007 ISBN 978-0-691-11485-9
- "Lahun Papyri: table texts". Retrieved 15 August 2016.
- Annette Imhausen, Jim Ritter: Mathematical Fragments, In: Marc Collier, Stephen Quirke: The UCL Lahun Papyri: Religious, Literary, Legal, Mathematical and Medical, Oxford 2004, ISBN 1-84171-572-7, 94-95
- "Lahun Papyri: table texts". Retrieved 15 August 2016.
- "Lahun Papyri: table texts". Retrieved 15 August 2016.
- Annette Imhausen, Jim Ritter: Mathematical Fragments, In: Marc Collier, Stephen Quirke: The UCL Lahun Papyri: Religious, Literary, Legal, Mathematical and Medical, Oxford 2004, ISBN 1-84171-572-7, 74–77
- ^ "Lahun Papyri: table texts". Retrieved 15 August 2016.
- Annette Imhausen, Jim Ritter: Mathematical Fragments, In: Marc Collier, Stephen Quirke: The UCL Lahun Papyri: Religious, Literary, Legal, Mathematical and Medical, Oxford 2004, ISBN 1-84171-572-7, 78–79
- "Lahun Papyri: table texts". Retrieved 15 August 2016.
- Annette Imhausen, Jim Ritter: Mathematical Fragments, In: Marc Collier, Stephen Quirke: The UCL Lahun Papyri: Religious, Literary, Legal, Mathematical and Medical, Oxford 2004, ISBN 1-84171-572-7, 90–91
- Imhausen, Annette, Ancient Egyptian Mathematics: New Perspectives on Old Sources, The Mathematical Intelligencer, Vol 28, Nr 1, 2006, pp. 19–27
External links
- John Legon: A Kahun Mathematical Fragment Archived 3 September 2012 at archive.today
- History of Egyptian fractions
- Medical Papyrus, UCL website
- The Kahun Gynaecological Papyrus
- "Kahun papyrus and Arithmetic Progressions". PlanetMath.
- "Egyptian fraction". PlanetMath.