Shown with a cast-on count of 5 stitches.  

• Row 1 (RS): K1, yo, k1, yo, k1, yo, k1, yo, k1 (9 sts).
• Rows 2, 4, 6, 8, 10, 12, 14, 16, and 18: Knit.
• Row 3: K1, yo, k3, yo, k1, yo, k3, yo, k1 (13 sts).
• Row 5: K1, yo, k5, yo, k1, yo, k5, yo, k1 (17 sts).
• Row 7: K1, yo, k7, yo, k1, yo, k7, yo, k1 (21 sts).
• Row 9: K1, yo, k9, yo, k1, yo, k9, yo, k1 (25 sts).
• Row 11: K1, yo, k11, yo, k1, yo, k11, yo, k1 (29 sts).
• Row 13: K1, yo, k13, yo, k1, yo, k13, yo, k1 (33 sts).
• Row 15: K1, yo, k15, yo, k1, yo, k15, yo, k1 (37 sts).
• Row 17: K1, yo, k1, [yo, k2tog] 8 times, yo, k1, yo, k1, [yo, k2tog] 8 times, yo, k1 (41 sts).