Last week, somebody on Twitter posted a link to this table from positiveintegers.org (I really apologise for not making a note of who it was). It was billed as a useful resource for designers because it lists all of the factors of the numbers between 101 and 200 so you know at a glance which numbers of stitches will fit to a particular stitch pattern.
But then it really got me thinking. What if you're working on something with a change in the number of stitches in a repeat. Let's say you have a sweater with a 2x2 rib at the bottom and a 7 stitch body pattern, you can find the number closest to the size you want that will give you both. Similarly if you want to decrease evenly, you can see how many decreases you can make and cross reference against the resulting number of stitches to check whether a second decrease of similar size is possible.
I should have been doing other things, so of course I looked through for the really useful numbers - those with a large number of factors. This was when I discovered something that probably everyone else knows: 168 is a really, really useful number. OK, so it doesn't have 5 or 10 as factors, nor does it have the largest number of factors in the range, but, if we can get over our having 5 fingers on each hand for a minute, it does have plenty to work with (16 in total) and it isn't a number that springs immediately to mind.
So will I be changing how I work out stitch counts? Well, in all honesty, probably not. I'm still firmly wedded to using a spreadsheet for grading as exact numbers of pattern repeats (particularly for larger numbers of stitches) don't always give the right interval between sizes and cross referencing is much quicker. I will however bookmark it as a starting point when looking to combine two stitch patterns.
Geeky mind dump over.