Zig Zag Rib Knitting Stitch

The stitches are knit through the back loop and create interesting zigzag effect of the twisted stockinette ribs

Cast on a multiple of 3 sts, + 1.
Row 1 (RS): Purl 1, * Knit tbl second stitch, then knit first stitch, and drop them both at the same time, purl 1; rep from * to end.
Row 2: Knit 1, * purl second stitch, then purl first stitch, and drop them both at the same time, knit 1; repeat from * to end.
Repeat these rows.