or buy at Payhip or LoveCrafts Pythagoras Tree represents Pythagoras Theorem: ‘The square on the hypotenuse is equal to the sum of the squares on the other two sides.’ In this case, the ‘squares on the other two sides’ are equal so, in knitting terms, that means that each small square has exactly half as many stitches to knit as the large square on the same triangle. There are five sizes of square, getting ever smaller. The design is like a fractal as the same pattern is repeated at smaller sizes. The afghan can be made in any yarn although the choice of yarn will dictate the finished size. The original was made in Aran weight yarn; the replacement was made using two strands of Double Knitting throughout. The instructions are extremely easy to follow. The afghan is worked entirely in garter stitch with the squares and triangles being knitted first and the background knitted on afterwards. The booklet includes a colouring sheet where you can plan your own colour combination. The original afghan was bought by the Mathematics Collection of the London Science Museum. The two versions are shown in the photos. Read the story of this afghan on Ravelry or on Woolly Thoughts web site. We also have a cushion pattern demonstrating Pythagoras Theorem in a different way