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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? SYLLABUS 
Schedule
Sunday
Jun 25  Sep 17 
7:30  9:00 PM ET
Jun 25  Sep 17
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 
Anna Meyers 
$380
(~$32/week)
$435 w/books

$380
(~$32/week)
CLOSED
With Books $435

Tuesday
Aug 1  Oct 17 
7:30  9:00 PM ET
Aug 1  Oct 17
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 
Eli Brottman 
$380
(~$32/week)
$435 w/books

$380
(~$32/week)
ENROLL
With Books $435

Friday
Sep 15  Dec 8 
7:30  9:00 PM ET
Sep 15  Dec 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 
Luís Finotti 
$380
(~$32/week)
$435 w/books

$380
(~$32/week)
ENROLL
With Books $435

Wednesday
Nov 1  Feb 7 
9:30  11:00 PM ET —
Nov 1  Feb 7
9:30  11:00 PM Eastern 8:30  10:00 PM Central 7:30  9:00 PM Mountain 6:30  8:00 PM Pacific Click here to see more time zones 
Carl Yerger 
$380
(~$32/week)
$435 w/books

$380
(~$32/week)
ENROLL
With Books $435

Sunday
Dec 10  Mar 10 
7:30  9:00 PM ET
Dec 10  Mar 10
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 
David Reynoso Valle 
$380
(~$32/week)
$435 w/books

$380
(~$32/week)
ENROLL
With Books $435

AoPS Holidays
There are no classes September 2‐4, October 31, November 20‐27, and December 21‐January 3, 2024.
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.
Related course: Introduction to Number Theory 