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Math 453: Elementary Theory of Numbers
Syllabus

Texts

  • Text: James Strayer, Elementary Number Theory, Waveland Press, 1994/2002, ISBN 1-57766-224-5
  • Alternate texts (available on library reserve):
    Kenneth Rosen, Elementary Number Theory and its Applications, 5th Edition, McGraw Hill, ISBN 0-201-87073-8.
    I. Niven, H. Zuckerman, H. Montgomery, An Introduction to the Theory of Numbers, 5th Edition, Wiley, ISBN 0471625469.

Sample Syllabus (based on Strayer)

  • Chapter 1: Divisibility and Factorization (8 hours)
    • Divisibility: Definition, properties, division algorithm, greatest integer function
    • Primes: Definition, Euclid's Theorem, Prime Number Theorem (statement only), Goldbach and Twin Primes conjectures, Fermat primes, Mersenne primes
    • The greatest common divisor: Definition, properties, Euclid's algorithm, linear combinations and the gcd
    • The least common multiple: Definition and properties,
    • The Fundamental Theorem of Arithmetic: Euclid's Lemma, canonical prime factorization, divisibility, gcd, and lcm in terms of prime factorizations
    • Primes in arithmetic progressions: Dirichlet's Theorem on primes in arithmetic progressions (statement only)
  • Chapter 2: Congruences (8 hours)
    • Definitions and basic properties, residue classes, complete residue systems, reduced residue systems
    • Linear congruences in one variable, Euclid's algorithm
    • Simultaneous linear congruences, Chinese Remainder Theorem
    • Wilson's Theorem
    • Fermat's Theorem, pseudoprimes and Carmichael numbers
    • Euler's Theorem
  • Chapter 3: Arithmetic functions (8 hours)
    • Arithmetic function, multiplicative functions: definitions and basic examples
    • The Moebius function, Moebius inversion formula
    • The Euler phi function, Carmichael conjecture
    • The number-of-divisors and sum-of-divisors functions
    • Perfect numbers, characterization of even perfect numbers
  • Chapter 4: Quadratic residues (4 - 6 hours)
    • Quadratic residues and nonresidues
    • The Legendre symbol: Definition and basic properties, Euler's Criterion, Gauss' Lemma
    • The law of quadratic reciprocity
  • Chapter 5: Primitive roots (4 - 6 hours)
    • The order of an integer
    • Primitive roots: Definition and properties,
    • The Primitive Root Theorem: Characterization of integers for which a primitive root exists
  • Additional Topics (8 - 12 hours): Selected from Chapters 6 - 8 of Strayer, or other sources. Possible choices include:
    • Continued fractions and rational approximations
    • Sums of squares
    • Pythagorean triples
    • Pell's equation
    • Partitions
    • Recurrences
    • Applications to primality testing
    • Application to cryptography

Last modified by A.J. Hildebrand; approved by R. Muncaster

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