Shown with a cast-on count of 4 stitches.  

• Row 1 (RS): K4.
• Row 2: P4.
• Row 3: K1, yo, k2, yo, k1 (6 sts).
• Row 4: P6.
• Row 5: K1, yo, k4, yo, k1 (8 sts).
• Row 6: P8.
• Row 7: K1, yo, k6, yo, k1 (10 sts).
• Rows 8, 10, 12, 14, 16, and 18: P10.
• Rows 9, 11, 13, 15, 17, and 19: K1, yo, p2tog, p2tog, k4, yo, k1.