fall 2026

putnam · practice sessions

Weekly training for the William Lowell Putnam Mathematical Competition: one technique per week, a short lecture, then problems.

the exam: Saturday, December 5, 2026 — four 90-minute sessions with breaks (new this year). Twelve problems, ten points each. MAA Putnam page
meetings: Thursdays 9:10–10:00 and Fridays 1:40–2:30 in Library 389 (one exception: Fri Nov 13 meets in Library 41)
The two sessions each week are identical
registration: Any Reed undergraduate can take the exam (at most four times). Email ormsbyk@reed.edu to get the registration link.
resources: Kedlaya's Putnam archive⋄CMU Putnam seminar handouts⋄Stanford Putnam/Pólya seminar⋄Northwestern's easy Putnam problems⋄AoPS Putnam forum
books: Gelca & Andreescu, Putnam and Beyond⋄Zeitz, The Art and Craft of Problem Solving⋄Engel, Problem-Solving Strategies

Each week has two identical sessions; come to whichever fits your schedule. A 15-minute mini-lecture on one technique, then 35 minutes of group work on a six-problem handout (two warm-ups, two easy Putnam problems, two hard take-homes). Solutions are posted after Friday's session.

These materials were drafted with the help of an AI assistant (Claude) and reviewed by me before practice sessions.

jump to this week ↓10 meetings

week 1

thu sep 24 /
fri sep 25

Induction, pigeonhole, and the extremal principle — and how to write a solution that scores
materialsnotes⋄handout
solutionssolutions
noteThu 9:10 or Fri 1:40 — same session both days

week 2

thu oct 1 /
fri oct 2

Invariants, monovariants, parity, and coloring
materialsnotes⋄handout

week 3

thu oct 8 /
fri oct 9

Polynomials: roots, Vieta, $a - b ∣ p (a) - p (b)$ , interpolation, growth
materialsnotes⋄handout

week 4

thu oct 15 /
fri oct 16

Number theory: congruences, orders, Fermat–Euler–Wilson, valuations
materialsnotes⋄handout

thu oct 22 /
fri oct 23break

Fall break — no sessions

week 5

thu oct 29 /
fri oct 30

Combinatorics: bijections, double counting, recursions, generating functions
materialsnotes⋄handout

week 6

thu nov 5 /
fri nov 6

Inequalities and analysis: AM–GM, Cauchy–Schwarz, Jensen, integrals, sequences, MVT
materialsnotes⋄handout

week 7

thu nov 12 /
fri nov 13

Linear algebra: determinants, eigenvalues, trace, rank, structured matrices
materialsnotes⋄handout
noteFriday Nov 13 meets in Library 41, not Library 389 (Thursday is in 389 as usual)

week 8

thu nov 19 /
fri nov 20

Probability, expectation, and games: indicators, symmetry, conditioning, strategies
materialsnotes⋄handout

thu nov 26 /
fri nov 27break

Thanksgiving — no sessions

week 9

thu dec 3 /
fri dec 4review

Exam week: the 2026 format, triage, writing for points, and a timed 35-minute mini-set
materialsnotes⋄handout
noteTake-home problems 4–6 are for after the exam if you like

exam

sat dec 5exam

The 87th Putnam — four 90-minute sessions, ROOM TBD. Bring blue/black pens and your Putnam ID number; no calculators, notes, or drawing tools.
noteRules and format