Shown with a cast-on count of 23 stitches.  

• Rows 1, 3, 5, 7, and 9 (WS): Purl.
• Row 2: K4, [yo, sl1-k2tog-psso, yo, k3] 3 times, k1.
• Row 4: K1, [yo, sl1-k2tog-psso, yo, k3] 3 times, yo, sl1-k2tog-psso, yo, k1.
• Row 6: K5, [yo, k1, yo, k5] 3 times (29 sts).
• Row 8: K2, [yo, k1, yo, k7] 3 times, yo, k1, yo, k2 (37 sts).
• Row 10: K8, [yo, k1, yo, k9] twice, yo, k1, yo, k8 (43 sts).