Shown with a cast-on count of 21 stitches.  

• Rows 1 and 21 (RS): [K1, p1] 10 times, k1.
• Rows 2 and 22: [K1, p1] 10 times, k1.
• Rows 3, 5, 7, 9, 11, 15, 17, and 19: K1, p1, k17, p1, k1.
• Rows 4, 6, 8, 10, 12, 14, 16, 18, and 20: K1, p19, k1.
• Row 13: K1 wrapping yarn twice, p1 wrapping yarn twice, k17 wrapping yarn twice, p1 wrapping yarn twice, k1 wrapping yarn twice.