l - - " i e~ , ,~ ,~e , , z , ]~ , i [ .~ - - - R o b i n W i l s o n I

Chinese Mathematics I Raymond Flood and Robin Wilson

C hinese mathemat ic ians have ap- pea red on a n u m b e r o f s tamps,

and the ones shown here i l lustrate mathemat ica l developments over many

centuries.

Zhang Heng [Chang Heng] ( 7 8 - 1 3 9 A D ) , inventor of the seismo- graph, was one of severa l Chinese

mathemat ic ians who devo ted a t tent ion

to finding the value of ~-. He p r o p o s e d the value ~ / ~ (approx imate ly 3.16), a va lue also found by Indian mathemat i - c ians a couple of centur ies earlier. The

Chinese fascinat ion with 7r r eached its c l imax with the work of Zu Changzhi [Tsu Ch 'ung -Ch ih ] ( 4 2 9 - 5 0 0 ) , who found that 7r lies be tween 3.1415926 and 3.1415927; the value given on the

s t amp is the average of these bounds. He also d iscovered the approx ima t ion 355/113, which also gives ~- cor rec t to

s ix dec imal places; this approx ima t ion was red iscovered in Europe over a t housand years later. Both of these

s t amps appea red in 1995. Two 20th-century mathemat ic ians

a p p e a r in ser ies of s t amps on Chinese

scientists , i ssued in 1988 and 1992. They are X i o n g Q i n g l a i , who made impor tan t contr ibut ions to meromor- phic and entire functions; and his stu-

dent , Hua Loo-Keng [Hua Luogeng] an outs tanding number - theo r i s t - - l e a -

tu red in our art icle in vol. 16 (1994),

no. 3, 36-46.

Raymond Flood

Department of Continuing Education

Kellogg College

Oxford, OX1 2JA

UK

Hua L o o - K e n g

Xiong Qinglai

Please send all submissions to

the Stamp Corner Editor,

Robin Wilson, Faculty of Mathematics,

The Open University, Milton Keynes, MK7 6AA, England Zhang Heng Z u Changzhi

THE MATHEMATICAL INTELLIGENCER �9 1998 SPRINGERWERLAG NEW YORK