Mideast Queries – p.1

QUERIES ON MIDDLE-EASTERN SOURCES

IN RECREATIONAL MATHEMATICS

DAVID SINGMASTER

Copyright ©2003 Professor David Singmaster

contact via http://puzzlemuseum.com

Last revised on 10 Oct 2002.

Last updated on 7 August 2013.

I am working on a history of recreational mathematics. I have found a number of topics which have Egyptian, Indian, Persian, Arabic or Turkish connections which I am gathering here for convenience in correspondence. Separate letters deal with Russian questions and with Oriental questions, i.e. China and Japan.

Some questions relate to the whole of the Middle East, while others are more specific to parts of it. I give the general questions first. Many of these concern situations where problems are known from China (and/or India) and Europe, but there are no Indian and Arabic (or just Arabic) sources known to me. That is, the apparent transmission from the Orient has a gap in it. There are also problems which appear quite fully developed in Fibonacci or Alcuin which seem as though they must have some earlier appearances, probably in Arabic, though Byzantine sources are also possible. There are also a few cases where transmission seems to have gone from Europe to the Orient. It is possible that transmission may have taken place along the Silk Roads of Central Asia and consequently left no trace in the Indian and Arabic cultures. I would be most grateful to anyone who can shed light on such transmission.

The recreational questions are discussed more fully in my Sources or the Queries thereto. I am currently working on the seventh preliminary edition of this.

GENERAL

MORRIS GAMES. The game known as Nine Men's Morris, Mill, Moule, Mühle, etc. is said to have been played at various places in the ancient world. A game board from -14C was found at Kurna, Egypt and boards from 1C occur at Mihintale, Ceylon. Are there other early examples? Are there any ancient written references? Murray's History of Chess mentions the Arabic game of qirq as (a kind of) morris and gives some 8C and 10C references. This becomes alquerque in Spain.

RIVER CROSSING PROBLEMS. These are first known in Alcuin, 9C, but I wonder if he learned these from some Middle Eastern source. Marcia Ascher has described many African versions, but it is not clear if these are ancient.

EULER CIRCUITS. Ascher has also described Euler Circuits in many cultures, but again we do not know if these are ancient. One pattern, of two crescents facing opposite directions but overlapping, is known as the 'Seal of Mahomet'. Does it occur in Arabic sources?

THE EXPLORER'S OR JEEP PROBLEM. Alcuin is also the earliest known example of trying to cross a desert – the Explorer's or Jeep Problem. His version is not too clear and the problem does not seem to reappear until Pacioli (c1500) and then the 20C! Alcuin's problem involves camels and again I wonder if there was a Middle Eastern source.

KNIGHT'S TOURS. The earliest known example is in an Sanskrit MS poem Kāvyālaʼnkāra , by Rudrata, c900, described in Murray's A History of Chess. However, an Arabic MS of 1141 gives tours which may derive from lost works of al-‘Adlī (c850) or aş-Şūlī (c920). Rudrata seems to be the only known early Indian source. Since chess originated in India, there ought to be more examples in early chess literature in India? Many problems based on the chessboard appear in the 19C, but in view of their naturalness, I wonder if some of these appear in earlier chess literature.

TANGRAMS. These became a fad in China c1810 and in Europe c1817 and the earliest appearance in the Far East appears to be early 18C in Japan, but with a different set of pieces. The only other early tangram-like puzzle seems to be the Loculus of Archimedes, known in the classical world from -3C to at least 6C. It has 14 pieces and is rather more complex than the Tangrams. Some of the Archimedes sources are two 17C Arabic MSS, so the Loculus may have been known to the Arabs and possibly they transmitted it to China?? Jerry Slocum has managed to track this back considerably in China and a book that I have just acquired indicates it was introduced to Europe in 1817.

In 1996 I noticed the ceiling of the room to the south of the Salon of the Ambassadors in the Alcazar of Seville. This 15C? ceiling was built by workmen influenced by the Moorish tradition and has 112 square wooden panels in a wide variety of rectilineal patterns. One panel has some diagonal lines and looks like it could be used as a 10 piece tangram-like puzzle. Since geometric patterns and panelling are common features of Arabic art, I wonder if there are any instances of such patterns being used for a tangram-like puzzle?

PYTHAGOREAN PROBLEMS. Fibonacci gives a Pythagorean problem of locating a Well Between Two Towers which shall be equidistant from the tops of the towers. Most Pythagorean problems already appear in Babylonian, Chinese or Indian sources, but I haven't seen this one before Fibonacci. Also the Broken Bamboo problem appears in Chinese and Indian sources, but I feel it may appear in Babylonian or Greek sources.

THE JOSEPHUS OR SURVIVOR PROBLEM. This has only a vague connection with Josephus, but may have its origins in the Roman custom of decimation. An article claims an Irish origin of the problem, c800, and gives early medieval forms called the Ludus Sanct Petri. It was certainly very popular in medieval and Renaissance Europe. Murray's History of Chess mentions 10 diagrams of this in an Arabic chess MS of c1370, possibly referring to a c1350 work. Murray asserts the problem is of Arabic origin. I have a reference to a 1659 Arabic version. Are there any other early Arabic sources?

EGYPTIAN FRACTIONS. Is there any attempt to show that every fraction can be written as a sum of distinct unit fractions before Fibonacci?

THE APPLE ORCHARD WITH THREE GUARDS PROBLEM involves a man taking apples from a garden and having to pay each of three guards something like half of his apples and half an apple more, leaving him with a given amount. An alternate version involves a travelling merchant who doubles his money and spends 1000 at each of three fairs, ending with no money. Both versions are common throughout medieval European mathematics and some occur in the Chiu Chang Suan Ching (c-150), in Sridhara (c900) and Bhaskara II (1150). An indeterminate form, usually known as the Monkey and Coconuts Problem, where we only know the final result (mod m), occurs in Mahavira (850) and then in Ozanam (1725) and reappears about 1900. Are there any Arabic or Persian versions of this problem? A different version has the i-th child receiving i plus 1/n of the remainder with all children getting the same amount. This appears in Fibonacci but it might be Arabic?

HALF + THIRD + NINTH, ETC. A common version of this is called The 17 Camels. Originally this problem was solved by dividing the camels in the proportion 1/2 : 1/3 : 1/9 and the fact that the fractions did not add up to 1 was ignored. Such problems occur already in the Rhind Papyrus and in the Bakhshali MS and in Chaturveda. Tartaglia is claimed to be the earliest to borrow an 18th camel, but I can't find it there. The problem in this form is often claimed to be of Arabic or Hindu origin.

CISTERN PROBLEMS. These go back to the Chiu Chang Suan Ching and Hero(n) of Alexandria. When do fanciful versions – e.g. ship with two sails or three animals eating a sheep – originate? Fibonacci gives the latter and the Byzantine Rechenbuch gives the former (with 5 sails), which Vogel states to be the earliest of this form. I have no earlier examples. However, the equivalent 'assembly' problems of the Chiu Chang Suan Ching also occur in Old Babylonian.

EACH DOUBLES THE OTHER'S MONEY TO MAKE ALL EQUAL. A version appears in Diophantos, then the problem occurs in Mahavira and Fibonacci. Are there other early examples?

SHARING COSTS. There are two common forms. The earlier involves men who work for part of the time and this occurs in Mahavira and Sridhara. The other concerns a man who digs part of a well – how much should he be paid? This occurs in al-Qazwini (1262) with several possible answers, but no resolution. Dell'Abbaco gives both forms with a resolution of a well problem. Are there other early examples?

CASTING OUT NINES. This is often attributed to the Hindus, but I have some references to Greek special uses of it by St. Hippolytus (c200) and Iamblichus (c325) though I haven't seen either source. I have read that Avicenna's attribution of it to the Hindus is a dubious interpretation. It appears in al-Khwārizmī (c820) and al-Uqlidīsī (952/953) as well as in Aryabhata II's Mahā-siddhānta.

THE CHESSBOARD PROBLEM. (which leads to 1 + 2 + 4 + 8 + ...) is often attributed to India, but my earliest sources are Arabic: al-Ya‘qūbī (c875) (described in Murray's History of Chess), al-Maş‘udi's Meadows of Gold (943), which doesn't relate the series to the chessboard) and al-Bīrūnī's Chronology of Ancient Nations (1000). Murray cites a 9 or 10C treatise on the problem by al-Missisī – does this exist? Is there any Indian or Persian material of relevance?

The use of 1, 2, 4, ... and 1, 3, 9, ... as weights occurs in Fibonacci but I feel there must be earlier examples. I have a reference to Tabari (c1075).

CHINESE RINGS. These are claimed to occur in Sung China (c11C) – but I have no references to such material. My first reference is Cardan (1550), but it must have been transmitted to Europe in some way.

MAGIC SQUARES. The Indian and Arabic history of Magic Squares is quite confused. A. N. Singh (Proc. ICM, 1936, pp. 275-276) refers to a c1C order 4 square by Nâgârjuna, but I know nothing more about this. There are many Indian and Arabic references that I have not been able to find – indeed some apparently are not extant – but it would take too long to list them here.

THE 100 FOWLS PROBLEM. appears in China c475 and recurs in Chinese works over the next centuries. In the 9C, it appears as a well developed problem in Alcuin (c800?), Mahavira (850) and Abu Kamil (c900). This is a remarkably rapid transmission. Abu Kamil implies the problem was well known. His comments and the rapidity of transmission lead me to wonder if there are earlier examples. The problem appears in the Bakhshali MS which may have been early enough to show transmission across north India??

SELLING DIFFERENT AMOUNTS AT THE SAME PRICES TO YIELD THE SAME AMOUNT appears in one form in Mahavira, Sridhara and Bhaskara. A simpler form occurs in Fibonacci and later European books. Are there any Arabic versions or other Indian ones?

CONJUNCTION OF PLANETS. This is a variant of the Chinese Remainder Theorem which appears in China and India. Are there any Arabic forms?

THE BLIND ABBESS AND HER NUNS. This occurs in an Arabic MS on chess in c1370. I then have Pacioli (c1500) and van Etten (1653 ed.). Are there other Arabic or medieval forms?

DILUTION PROBLEMS. A one stage version is in the Rhind Papyrus and a four stage version is in the Bakhshali MS. My next example is Tartaglia.

THE APPLESELLER'S PROBLEM, involving combining amounts and prices incorrectly, appears in Alcuin (9C) and Ibn Ezra (c1150), then Fibonacci, etc. Are there Arabic or Indian versions?

THE LAZY WORKER, who gains for each day he works and forfeits for days he doesn't work, appears in al-Karkhi (c1010), Tabari (c1075) and Fibonacci, etc. Are there other Arabic or perhaps Greek or Indian sources?

LIAR PARADOX. Do the Liar or similar paradoxes occur in Arabic or Indian works?

THREE MEN WITH SPOTS ON FOREHEADS. This problem appears in the US, c1935, attributed to Alonzo Church. A book on Palestinian stories says it was a well known folk story when it was heard before 1948, though the solution was based on symmetry rather than logic. The version known as Forty Unfaithful Wives has a Central Asian setting but may be a 20C invention.

STRANGE FAMILIES – e.g. men marrying each other's sister or daughter – occur in Alcuin, Abbott Albert and a c1430 Hebrew text. Are there earlier versions? There is a riddle about a strange family attributed to the Queen of Sheba, but I can't find any version of her riddles.

SNAIL CLIMBING OUT OF A WELL. This seems to derive from the habit of expressing velocity by unit fractions – e.g. the snail goes at a rate of +1/2 -1/3. Such problems occur in Chaturveda, Mahavira, Sridhara and Fibonacci. But in Europe of c1370, the idea that the 1/2 was in the day and the 1/3 was in the night was being treated carefully. Are there earlier examples where the rates are treated alternately?

SOLOMON'S SEAL. I have recently seen the string and bead puzzle known as Solomon's Seal claimed as an African puzzle, but with no reference. Can anyone supply details?

WIRE PUZZLES first seem to appear in the West in the late 19C. They were and are popular in India and China, but I don't know any early sources except for the Chinese Rings.

PUZZLE RINGS are believed to be Middle Eastern in origin. Are there any sources? There is a 17C example in the British Museum.

INDIA

I have had difficulty in communicating with the National Institute of Sciences, New Delhi. They haven't responded to my letters – do they exist? I wanted to get the bibliography by Sen from them. This may have been obsoleted by Rahman's Bibliography, published by the Indian National Science Academy in New Delhi. I have recently received a copy of Rahman.

I'd like to get copies of the following:

Colebrooke, H, T. Algebra, with Arithmetic and Mensuration from the Sanscrit of Brahmagupta and Bhascara. (Originally Murray, London, 1817.) Annotated by H. C. Banerji, Calcutta, 1893 & 1927; Kitab Mahal, Allahabad, 1967. (I have a reprint of the original ed. I would like a copy of the annotated ed.)