Shown with a cast-on count of 24 stitches.  

• Row 1 (RS): K1, ctr dbl inc, k1, *yo, ssk, k1, k2tog, yo, k1, repeat from * to last 3 sts, ssk, k1 (multiple of 6 sts, plus 7).
• Rows 2, 4, 6, 8, 10, 12, 14, 16, 18, and 20: Purl.
• Row 3: K1, ctr dbl inc, k3, *yo, k1, k3tog, k1, yo, k1, repeat from * to last 8 sts, yo, k1, k3tog, k1, yo, ssk, k1 (multiple of 6 sts, plus 14).
• Row 5: K1, ctr dbl inc, k2, ssk, k1, *k2tog, yo, k1, yo, ssk, k1, repeat from * to last 7 sts, k2tog, yo, k1, yo, k1, ssk, k1 (multiple of 6 sts, plus 15).
• Row 7: K1, ctr dbl inc, k1, k2tog, yo, k1, k3tog, *k1, yo, k1, yo, k1, k3tog, repeat from * to last 6 sts, k1, yo, k1, yo, k1, ssk, k1 (multiple of 6 sts, plus 16).
• Row 9: K1, ctr dbl inc, k1, *yo, ssk, k1, k2tog, yo, k1, repeat from * to last 7 sts, yo, k2tog, k2, ssk, k1 (multiple of 6 sts, plus 11).
• Row 11: K1, ctr dbl inc, k3, *yo, k1, k3tog, k1, yo, k1, repeat from * to last 6 sts, yo, k1, k2tog, ssk, k1 (multiple of 6 sts, plus 12).
• Row 13: K1, ctr dbl inc, k1, yo, k1, yo, ssk, k1, *k2tog, yo, k1, yo, ssk, k1, repeat from * to last 5 sts, k2tog, ssk, k1 (multiple of 6 sts, plus 13).
• Row 15: K1, ctr dbl inc, k1, k2tog, *k1, yo, k1, yo, k1, k3tog, repeat from * to last 8 sts, k1, yo, k1, yo, k1, k2tog, ssk, k1 (multiple of 6 sts, plus 14).
• Row 17: K1, ctr dbl inc, k1, k2tog, yo, k1, *yo, ssk, k1, k2tog, yo, k1, repeat from * to last 8 sts, yo, ssk, k1, k2tog, yo, ssk, k1 (multiple of 6 sts, plus 15).
• Row 19: K1, ctr dbl inc, k2, k2tog, k1, yo, k1, *yo, k1, k3tog, k1, yo, k1, repeat from * to last 7 sts, yo, k1, k2tog, k1, ssk, k1 (multiple of 6 sts, plus 16).