Shown with a cast-on count of 15 stitches.  

• Round 1: *P3, yo, k3tog, yo, k3, yo, k2, ssk, yo, ssk, yo, repeat from * (16 sts).
• Rounds 2 and 10: *P3, k13, repeat from *.
• Round 3: *P3, yo, k2tog, yo, k1, yo, k2, ssk, yo, k2, ssk, yo, ssk, yo, repeat from * (18 sts).
• Rounds 4, 6, 12, and 14: *P3, k15, repeat from *.
• Round 5: *P3, yo, k2tog, yo, k3, yo, k2, ssk, ssk, ssk, yo, ssk, yo, repeat from *.
• Round 7: *P3, yo, k2tog, yo, k2tog, k2, yo, k1, yo, sl1-k2tog-psso, sl1-k2tog-psso, ssk, yo, repeat from * (16 sts).
• Round 8: *P3, k9, k2tog, k2, repeat from * (15 sts).
• Round 9: *P3, yo, k2tog, yo, k2tog, k2, yo, k3, yo, sl1-k2tog-psso, yo, repeat from * (16 sts).
• Round 11: *P3, yo, k2tog, yo, k2tog, k2, yo, k2tog, k2, yo, k1, yo, ssk, yo, repeat from * (18 sts).
• Round 13: *P3, yo, k2tog, yo, [k2tog] 3 times, k2, yo, k3, yo, ssk, yo, repeat from *.
• Round 15: *P3, yo, k2tog, [k3tog] twice, yo, k1, yo, k2, ssk, yo, ssk, yo, repeat from * (16 sts).
• Round 16: P3, k2, k2tog, k9 (15 sts).