I don't know the correct name for this stitch but it's been around forever and I've loved it for just as long. Here is my version, unvented I'm sure, but it's been around so long I don't think we could know who invented it anyway.

Abbreviations

K= Knit
P= Purl
Sl2= Slip 2 sts

Method

I'll make reference to the colours in the sample above but you can knit this stitch in any colours, of course!

Cast on a number of stitches divisible by 8 + 6 extra

Row 1: Using blue, K

Row 2: Using blue, P

Rows 3, 5 and 7: Using light green, (K6, sl2 purlways) to last 6 sts, K6

Rows 4, 6 and 8: Using light green, (p6, sl2 purlways) to last 6 sts, p6

Rows 9 and 10: Rep rows 1 and 2

Rows 11, 13 and 15: Using light green, K3, Sl 2 purlways (K6, sl2 purlways) to last 3 sts, K3

Rows 12, 14 and 16: Using light green, p3, Sl 2 purlways (p6, sl2 purlways) to last 3 sts, p3

Repeat these 16 rows to form pattern.

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