NIM

how to win the matchstick game: groups of 8, 4, 2, 1, worked examples and the losing triples

Built as a memo rather than a table: the thing worth hanging it up for reads across the room, with the full reference in smaller type below it.

Three sizes in one archive — from a sheet on the fridge to a poster on the wall.

Formats: A4 · A3 · A2
What you get: Print-ready PDFs, one per size, with every letterform converted to outlines — nothing to install, nothing to shift.
Subject: maths · everyone · memo · classroom

Two players take turns removing matches from any one heap: at least one, up to the whole heap. A turn cannot be skipped. Whoever takes the last match wins, unless agreed otherwise.

1 · 3 · 5 · 7: THE FIRST PLAYER LOSES

Heaps 1 · 3 · 5 · 7, 16 matches in all. In groups: 3 = 2 + 1, 5 = 4 + 1, 7 = 4 + 2 + 1. Groups of 4: 2, of 2: 2, of 1: 4. Everything is paired. So whoever moves first loses to an opponent who knows the rule, whether the last match wins or loses. Offer your opponent the first move.

On the sheet

Two players take turns removing matches from any one heap: at least one, up to the whole heap. A turn cannot be skipped. Whoever takes the last match wins, unless agreed otherwise.
Colour carries meaning, but meaning never rests on colour alone — the sheet reads in black and white.
Nothing about how it was made: the sheet carries only what the reader needs.

Printing

Three sizes in the archive: A4 — 210×297 mm, A3 — 297×420 mm, A2 — 420×594 mm.
All text is converted to outlines. No fonts to install, and nothing shifts on another machine.
White background and sparing fills — it prints on a home printer without draining the cartridge.
Margins of at least 10 mm: a home printer cannot print to the edge.
No stroke thinner than 0.3 mm, so nothing disappears in print.

Why the numbers can be trusted. Every countable number here is computed from data rather than typed in, and the sheet must pass 5 independent checks before it is allowed to build — how many items there are, the order they come in, and the claim in the highlighted box itself. If one fails, there is no file.

NIM

1 · 3 · 5 · 7: THE FIRST PLAYER LOSES

On the sheet

Printing

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