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Lahun Mathematical Papyri

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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.[1]

Fragments

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The mathematical texts most commented on are usually named:

  • Lahun IV.2 (or Kahun IV.2) (UC 32159[2]): 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.[3]
  • Lahun IV.3 (or Kahun IV.3) (UC 32160[4]) contains numbers in arithmetical progression and a problem very much like problem 40 of the Rhind Mathematical Papyrus.[3][5][6] Another problem on this fragment computes the volume of a cylindrical granary.[7] 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.[8]
  • Lahun XLV.1 (or Kahun XLV.1) (UC 32161[9]) contains a group of very large numbers (hundreds of thousands).[3][10]
  • Lahun LV.3 (or Kahun LV.3) (UC 32134A[11] and UC 32134B[12]) 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).[3][13]
  • Lahun LV.4 (or Kahun LV.4) (UC 32162[14]) contains what seems to be an area computation and a problem concerning the value of ducks, geese and cranes.[3][15] 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.[14]
  • Unnamed fragment (UC 32118B[16]). This is a fragmentary piece.[17]

2/n tables

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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.[18] 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

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References

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  1. ^ The Lahun Papyri at University College London
  2. ^ "Lahun Papyri: table texts". Retrieved 15 August 2016.
  3. ^ a b c d e 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
  4. ^ "Lahun Papyri: table texts". Retrieved 15 August 2016.
  5. ^ 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
  6. ^ Legon, J., A Kahun mathematical fragment, retrieved from [1] Archived 3 September 2012 at archive.today, based on Discussions in Egyptology 24 (1992), p. 21–24
  7. ^ Gay Robins and Charles Shute, "The Rhind Mathematical Papyrus", British Museum Press, Dover Reprint, 1987.
  8. ^ 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
  9. ^ "Lahun Papyri: table texts". Retrieved 15 August 2016.
  10. ^ 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
  11. ^ "Lahun Papyri: table texts". Retrieved 15 August 2016.
  12. ^ "Lahun Papyri: table texts". Retrieved 15 August 2016.
  13. ^ 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
  14. ^ a b "Lahun Papyri: table texts". Retrieved 15 August 2016.
  15. ^ 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
  16. ^ "Lahun Papyri: table texts". Retrieved 15 August 2016.
  17. ^ 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
  18. ^ Imhausen, Annette, Ancient Egyptian Mathematics: New Perspectives on Old Sources, The Mathematical Intelligencer, Vol 28, Nr 1, 2006, pp. 19–27
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