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Introduction to Number TheoryFundamental principles of number theory, including primes and composites, divisors and multiples, divisibility, remainders, modular arithmetic, and number bases. 
12 weeks 
12 weeks ARE YOU READY? DO YOU NEED THIS? 
Schedule
Thursday
May 16  Aug 8 
7:30  9:00
PM ET
May 16  Aug 8
7:30  9:00 PM Eastern 6:30  8:00 PM Central 5:30  7:00 PM Mountain 4:30  6:00 PM Pacific Click here to see more time zones 
Jeffrey Hankins 
$325
$376 w/books

$325
CLOSED
With Books $376

Tuesday
Jun 11  Aug 27 
7:30  9:00
PM ET
Jun 11  Aug 27
7:30  9:00 PM Eastern 6:30  8:00 PM Central 5:30  7:00 PM Mountain 4:30  6:00 PM Pacific Click here to see more time zones 
Kevin Carlson 
$325
$376 w/books

$325
CLOSED
With Books $376

Wednesday
Jun 12  Aug 28 
7:30  9:00
PM ET
Jun 12  Aug 28
7:30  9:00 PM Eastern 6:30  8:00 PM Central 5:30  7:00 PM Mountain 4:30  6:00 PM Pacific Click here to see more time zones 
Heather Finotti 
$325
$376 w/books

$325
CLOSED
With Books $376

Monday
Jun 24  Sep 16 
7:30  9:00
PM ET
Jun 24  Sep 16
7:30  9:00 PM Eastern 6:30  8:00 PM Central 5:30  7:00 PM Mountain 4:30  6:00 PM Pacific Click here to see more time zones 
Homero Renato Gallegos Ruiz 
$325
$376 w/books

$325
CLOSED
With Books $376

Thursday
Sep 5  Nov 21 
7:30  9:00
PM ET
Sep 5  Nov 21
7:30  9:00 PM Eastern 6:30  8:00 PM Central 5:30  7:00 PM Mountain 4:30  6:00 PM Pacific Click here to see more time zones 
Alyssa Zisk 
$325
$376 w/books

$325
ENROLL
With Books $376

Friday
Sep 20  Dec 13 
7:30  9:00
PM ET
Sep 20  Dec 13
7:30  9:00 PM Eastern 6:30  8:00 PM Central 5:30  7:00 PM Mountain 4:30  6:00 PM Pacific Click here to see more time zones 
Eric Wofsey 
$325
$376 w/books

$325
ENROLL
With Books $376

Spring 2020  This course will be offered in Spring 2020. Click here to join our mailing list to be notified when the course schedule is available. 
AoPS Holidays
There are no classes September 1–2, November 25–December 1, or December 21–January 3.
Who Should Take?
This course is appropriate for students in grades 69 who have mastered basic algebra up through solving linear equations and manipulating multivariable expressions. Students who have completed our Introduction to Algebra A course should have sufficient background. Students who are already proficient with modular arithmetic and basic Diophantine equations do not need this course. This course is roughly the same difficulty as our Introduction to Counting and Probability class. For those preparing for contests, this course should help with MATHCOUNTS and the AMC 8/10/12 tests.Lessons
Lesson 1  Integers, Fractions, Decimals, and Number Bases 
Lesson 2  Base Number Arithmetic 
Lesson 3  Multiples, Divisors, and Prime Numbers 
Lesson 4  Common Factors, Common Multiples, Euclidean Algorithm 
Lesson 5  Divisor Problems, More with the Euclidean Algorithm 
Lesson 6  Factorials, Special Integers, Algebra with Integers 
Lesson 7  Units Digit, Introduction to Modular Arithmetic 
Lesson 8  Calculations with Modular Arithmetic 
Lesson 9  Divisibility Rules and Multiplicative Inverses 
Lesson 10  Multiplicative Inverses, Solving Linear Congruences 
Lesson 11  Systems of Linear Congruences and the Chinese Remainder Theorem 
Lesson 12  Number Sense and Applications of Number Theory 
Required Textbook
Introduction to Number Theory
A thorough introduction for students in grades 710 to topics in number theory such as primes & composites, multiples & divisors, prime factorization and its uses, base numbers, modular arithmetic, divisibility rules, linear congruences, how to develop number sense, and more.
