Number Theory: Structures, Examples, and Problems

 
About the Authors
Dorin Andrica 
received his Ph.D in 1992 from “Babe
ş
-Bolyai” University in 
Cluj-Napoca, Romania; his thesis treated critical points and applications to the 
geometry of differentiable submanifolds. Professor Andrica has been chairman 
of the Geometry Division at “Babe
ş
-Bolyai” University since 1995 and head of 
the Department of Pure Mathematics at the same University since 2007. He has 
written and contributed to numerous mathematics textbooks, problem books, 
articles and scientific papers at various levels. Dorin has been an invited lecturer 
at university conferences around the world: Austria, Bulgaria, Czech Republic, 
Egypt, France, Germany, Greece, Italy, the Netherlands, Portugal, Serbia, Turkey, 
and the USA. Dorin is a member of the Romanian Committee for the Mathematics 
Olympiad and is a member on the editorial boards of several international journals. 
Also, he is well known for his conjecture about consecutive primes called 
“Andrica’s Conjecture one of the most important open problems in Number 
Theory”. Dorin has been a regular faculty member at the Canada–USA Mathcamps 
(2001–2005) and at the AwesomeMath Summer Program (AMSP) since 2006. 

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Birkhäuser
Boston
•
Basel
•
Berlin
Titu Andreescu
Number Theory
Structures, Examples, and Problems
Dorin Andrica

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Titu Andreescu
University of Texas at Dallas
2601 N. Floyd Road, FN 33
Richardson, TX 75002, USA
[e-mail]
Dorin Andrica
and Computer Science
Faculty of Mathematics 
“Babe -Bolyai” University
Str. Kogalniceanu 1
3400 Cluj-Napoca, Romania
[e-mail]
Printed on acid-free paper.
www.birkhauser.com
and Mathematics Education
ISBN: 978-0-8176-3245-8
e-ISBN: 978-0-8176-4645-5
DOI: 10.1007/b11856
Library of Congress Control Number: 2009921128
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Business Media, LLC 2009
Mathematics Subject Classification (2000): 11A05, 11A07, 11A15, 11A25, 11A25, 11B37, 11B39,
Cover Design by Joseph Sherman
Department of Science
ş
11B65, 11D04, 11D09, 11D25

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Die ganzen Zahlen hat der liebe Gott gemacht, alles andere ist Menschenwerk.
God made the integers, all else is the work of man.
Leopold Kronecker

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