Thirty-six squares - one in the first colour, two in the second, three in the third, etc. Adding these numbers together gives the sequence of Triangular Numbers. When you get to 8 the whole shape forms a 6 x 6 square - a Square Number and a Triangular Number coincide.

If you were to keep going, when would this happen again? See our Data Log afghan to find out.

One photo shows the squares spiralling from the centre; in the other they spiral inwards.

This pattern is also available in our 12 Pillows of Wisdom ebook.