# F Number – Fibonacci is not a dirty word!!

For a while now I have been aware of the correlation between knitting and mathematics. As knitters we are constantly counting stitches and rows and memorizing patterns.

Recently I bought The book, Stitch ‘n Bitch: Superstar Knitting and have been reading it like it was a mystery novel. The biggest plot twist for me was a chapter devoted to the Fibonacci Sequence. It sounds like something out of The Da Vinci code and actually it is! The Da Vinci Code examines the F Sequence as the main character uses it to crack a code left by a deceased museum curator.

Your high-school or college teachers probably told you about the F sequence or F numbers but most of us never thought we would ever find a practical use for them in our everyday lives.

Biologists can probably tell you the significance of the F numbers as they are present in almost every plant. The ever elusive four leaf clover is elusive because four is not a F number. You see flower petals, seeds and leaves come in quantities of: one, two, three, five, eight, thirteen, twenty one, thirty two, fifty three, eighty five … Do you see a pattern? It is probably not coincidence that these numbers have such a strong correlation to nature since they can also be used to create an aesthetically pleasing set of “random” stripes for knitters.

After ready my F Sequence chapter in Stitch ‘n Bitch, I decided to give it a try with a couple of baby blankets I had planned to make. I love the look of random stripes but my random stripes never looked good like the ones in the magazines. What did they know that I didn’t? The F sequence!

OK the f sequence numbers are found by adding the last number to the one in front of it. So if you start with one then the next number is one (the number before) plus the number before it (zero). So now you have one as your first number and one again as your second number. Our third number is one plus one. Now we have 1, 1, 2. And you can go on calculating the F numbers from there. The official F numbers are:
1,1,2,3,5,8,13,21,34 …

You can also use the same formula used to find the F numbers and start with a random number like four which is not an official F number.
4,4,8,12,20,32,52…
But notice that these numbers are all corresponding with the F numbers.

I chose to use these numbers to count my pattern repeats in my blanket. My repeats were four rows long. But instead of counting row I counted the repeats. One repeat then four rows of another color then two repeats of my next color then three repeats of the last color petting the F numbers guide me. I chose to start again at one repeating from the beginning each time but you also can reverse the patern until you are back at one again.
To make sure my 1 repeat row of knitting wasn’t always the same color I decided to use 5 colors but only 4 F numbers so that my colors shifted through the pattern.

Not every striped blanket I see uses the F numbers to decide the thickness of each stripe and I haven’t figured out what mathematical formula they are using but for once I created a striped blanket that looks random and nice at the same time.