About David Seff

David Seff is a successful professor with over four decades of experience in the classroom. With a focus within Mathematics, David has instructed students in the areas of Calculus, Geometry, Algebra, Probability and Statistics, and Number Theory. With a professor at New York University, Dr. Earl Glenn Whitehead as the main author, he co-authored a graduate level text, used at New York University, entitled Constructive Combinatorics.

Early in his career, David Seff served as an Adjunct Lecturer at City College, Baruch College, and other colleges in the New York City Metropolitan area. During this time he also served as a Project Leader and Programmer Analyst with Chase Manhattan Bank. In this role, David wrote special utilities to recover securities data from crashed main from hard-disk when backup tapes had been written over. His expertise helped save the company from a potential risk of several billion dollars. In addition, he enhanced and maintained the Securities Tracking and Reporting Systems, among other systems as well.


David Seff is a graduate of New York University, The Courant Institute of Mathematical Sciences where he earned his Masters of Sciences in Mathematics. David Seff also earned MPhil and PhD degrees in math from the Graduate Center of the City University of New York. David previously had attended Yeshiva University where he received his Bachelor of Arts degree in Mathematics and Physics as well as a Masters of Arts in History.  While in high school he was one of hundred students chosen nationally by the National science Foundation to take graduate level courses in mathematics, and as a freshman in college, received one of the top 100 scores nationally on the prestigious Putnam Mathematics Competition.  He is the only person in the history of Yeshiva University to be nominated for the senior math award as a freshman, but was not given the award until he was a senior.

Professional Overview

David later transitioned to Guardian Life Insurance where he worked as a Technical Specialist and Systems Development. David Seff was one of several programmers involved in developing and testing the entire Y2K testing procedures for the company. While working on this project, David volunteered to teach several seminars to other programmers on newly developed programming enhancements for the turn of the century, thereby saving the company tens of thousands of dollars. David also coded new products and maintained old products for New Business Illustrations and performed actuarial programming involving interpreting statistical and mathematical formulae, utilizing special coding techniques to insure six-digit precision and no internal or rounding.

Teaching Experience

For several years, David Seff also served as an Adjunct Lecturer at Touro College, while working with Guardian, teaching night classes. Eventually, after over a decade-long tenure with the life insurance firm, David Seff returned to teaching at Kingsborough Community College and then Brooklyn College teaching Calculus and Graduate Math for Secondary School Teachers among other classes.

For nearly three decades, David Seff designed and taught several courses in math and physics at the New School in the evening math and science department, until the evening science department was disbanded.  He taught a course called “Fun With Math” which had a prerequisite of “a distaste for mathematics” which had full enrollment and rave reviews for years.  In this course, he showed many things that seem counter-intuitive and showed how and why they exist.  For example, he showed the students how to make a piece of paper that actually only has one side and a rectangular array of numbers which when added up first by rows and then by columns gives one sum, but when added first by columns and then rows gives a different sums—that is, it is a bunch of numbers whose sum changes if the order in which they are added up changes!  He also showed them numbers bigger than infinity and numerous mathematical systems that contain no numbers at all!

For some problems of interest, see attachments, “The Snake Problem,” and “Snake Problem Notes” on his Tutoring Website.

David Seff also taught other math courses such as Elementary Number Theory and Non-Euclidean Geometry.  In physics, he taught, “Light, Lasers, and Optics” as well as “Color, Beauty, and Light,” a special physics course for art majors.  In 1998, Professor Seff was awarded a faculty development grant, given to only one faculty member in each division, to develop a multi-media version of his class.