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2025-07-O1 Class

Lessons

If you are a prospective student, please join the other O1 class (2026-O1).

Chapter Week Code Topic Date
Proofs 1 P1 Proof and Contradiction Jul 27*
2 P2 Induction Aug 03*
Strategy 3 S1 Try Small Cases Aug 10*
4 S2 Case Bashing & Pigeonhole Principle Aug 17*
5 S3 Extremal Principle Aug 24*
Combinatorics 6 C1 Counting & Bijections Aug 31*
7 C2 Double Counting & Invariants Sep 07
8 C3 Graph Theory Sep 14
Number Theory 9 N1 Divisibility and Primes Sep 21*
10 N2 Modular Arithmetic Sep 28
11 N3 Diophantine Equations & Constructions Oct 05
Algebra 12 A1 Polynomials, Sequences, Graphs Oct 12*
13 A2 Inequalities Oct 19
14 A3 Functional Equations Oct 26
Geometry 15 G1 Angle and Length Chasing Nov 02*
16 G2 Radical Axis & Triangle Centres Nov 09
17 G3 Coord and Trig Bashing Nov 16
Strategy 18 S4 Backsolving Nov 23*
19 S5 Notation, Representation, and Visualisation Nov 30
20 S6 Problem Exploration & Training Dec 07

2026

The second half of this course will be focused on applied the theory, techniques, and strategies learned in the first half of the course to problems.

Chapter Week Code Topic Date
Proofs 21 P1 Proof and Contradiction Feb 15
22 P2 Induction Feb 22
Strategy 23 S1 Try Small Cases Mar 01
24 S2 Case Bashing & Pigeonhole Principle Mar 08
25 S3 Extremal Principle Mar 15
Combinatorics 26 C1 Counting & Bijections Mar 22
27 C2 Double Counting & Invariants Mar 29
28 C3 Graph Theory Apr 05
Number Theory 29 N1 Divisibility and Primes Apr 12
30 N2 Modular Arithmetic Apr 19
31 N3 Diophantine Equations & Constructions Apr 26
Algebra 32 A1 Polynomials, Sequences, Graphs May 03
33 A2 Inequalities May 10
34 A3 Functional Equations May 17
Geometry 35 G1 Angle and Length Chasing May 24
36 G2 Radical Axis & Triangle Centres May 31
37 G3 Coord and Trig Bashing Jun 07
Strategy 38 S4 Backsolving Jun 14
39 S5 Notation, Representation, and Visualisation Jun 21
40 S6 Problem Exploration & Training Jun 28