Knitted Cable Stitch.
Abbreviations:
3/3 RC = (3 over 3 right cross) 3 sts to cable needle and hold to the back of work, k3 then k3 from the cable needle.
3/3 LC = (3 over 3 left cross) 3 sts to cable needle and hold to the front of work, k3 then k3 from the cable needle.
Cable Panel: 13 stitch panel
Row 1 (RS): k6, p1, k6
Rows 2 and all even rows: p6, k1, p6
Row 3: 3/3 RC, p1, 3/3 LC
Row 5: Repeat Row 1
Row 6: Repeat Row 2
6 rows makeup up the pattern