About the Course

Elementary Number Theory

  • All Grades
  • CTY-Level
  • Individually Paced

Gain an introduction to the deep theory of integers, with special focus on the properties of prime numbers and integer or rational solutions to equations. 

You’ll cover topics aligned with Johns Hopkins University’s third-year Elementary Number Theory course as you focus on detailed exploration of topics such as divisibility, unique factorization, congruences, primitive roots, Diophantine equations, and proof techniques. Historical background for various problems will be provided throughout the course, and prime numbers and elliptic curves will be studied with applications to cryptography.

Graded assessments include homework, chapter exams, and cumulative tests that you can prepare for with your instructor during one-on-one review sessions in addition to their learning support throughout the course.

The recommended length of enrollment for this course is 6 months.

Time Commitment: 7-9 hours per week (7-9 hours independent work).

Students may enroll in this course at any time during the year.

Classes

Enrollment and tuition are time-based—students may enroll in a course by selecting an open class below. Students will progress at their own pace, with guidance from instructors who strive to meet individual needs. Note: You will need to have an active CTY Account to complete registration through MyCTY.
Synchronous class meetings typically last about an hour.

3 Months

3 months
Choose your start date
$885

6 Months

6 months
Choose your start date
$1715

Testing and Prerequisites

  Math Verbal
Required Level CTY-Level Not required
Check your eligibility using existing test scores If you do not have existing test scores:

Students must achieve qualifying scores on an advanced assessment to be eligible for CTY programs. If you don’t have qualifying scores, you have several different testing options. We’ll help you find the right option for your situation.

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Course Prerequisites

Elementary Number Theory requires:

1 prerequisite

Successful completion of Linear Algebra and Introduction to Abstract Math or the equivalent

Cost and Financial Aid

  • Tuition
    • Varies
  • Application fee
    • Nonrefundable Application Fee - $15 (Waived for financial aid applicants)
    • Nonrefundable International Fee - $20 (outside US only)
Financial Aid is available

We are committed to serving all talented youth regardless of financial circumstances. Financial assistance is available based on need.

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Course Materials

Please acquire all course materials by the course start date. If you have questions about these materials or difficulty locating them, please contact ctyinfo@jhu.edu.
 

Book Title: A Friendly Introduction to Number Theory, 4th edition
Author: Joseph H. Silverman
ISBN-13: 978-0321816191
ISBN-10: 0321816196

  • A proctor

Technical Requirements

This course requires a computer with high-speed Internet access and an up-to-date web browser such as Chrome or Firefox. You must be able to communicate with the instructor via email. Visit the Technical Requirements and Support page for more details.

This course uses a virtual classroom for instructor-student communication. The classroom works on standard computers with the Zoom desktop client, and on tablets or handhelds that support the Zoom Mobile app. Recorded meetings can only be viewed on a computer with the Zoom desktop client installed. The Zoom desktop client and Zoom Mobile App are both free to download.

Most course lectures may be viewed on mobile devices, but some assignments and quizzes must be completed on a desktop or laptop computer.

Adobe Acrobat Reader is needed to fill PDFs in this course. Download the latest version of Adobe Acrobat Reader for free.

Chromebooks are not recommended due to required downloading of specialized software. While Chromebook can be used to progress through the course, all exams must be completed on a PC or Mac.

You will need to install Respondus LockDown Browser proctoring software for designated assessments. View system requirements.

Terms & Conditions

Students may interact in online classrooms and meetings that include peers, instructors, and occasional special guests.

About Mathematics at CTY

Our online Mathematics courses—spanning elementary through college-level curricula—cover a wide range of topics, from algebra and geometry to chess, cryptology, and AP Calculus and are guided by expert instructors. You’ll join group sessions with classmates to ensure you stay on track with challenging course content. Whether you’re looking for pure math fun and enrichment, to move up the math ladder and advance your honors and AP (and beyond) academic standing, or to train for mathematics competitions, there’s a CTY course that’s right for you.

New math enrichment courses available!

Explore our new math enrichment courses, including Excursions in Pre-algebra, Mathematical Modeling, and Introduction to Logic and Proofs.

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