A pin cushion made out of five colours. Oversized, for blocking pins (or, I guess, a really impressive collection of straight pins) with an arm strap. Cushion is worked in spiral rounds, strap is worked in rows.

In graph theory: taking the colour blocks as planes, the line graph is K_5, drawn on a torus with no crossings. (Non-jargon explanation is in the pattern.)

Gauge is highly negotiable, but use tight, small stitches, because you’ll want to stuff it firmly. 100% cotton is nice because it doesn’t stretch under tension.

Tag: math