Shown with a cast-on count of 37 stitches.  

• Rows 1 and 31 (RS): P4, *k2tog, yo, k1, yo, ssk, p7, repeat from * to last 9 sts, k2tog, yo, k1, yo, ssk, p4.
• Rows 2, 6, 8, 12, 14, 18, 20, 24, 26, 30, 32, 36, and 38: Purl.
• Rows 3, 5, 9, 11, 15, 17, 21, 23, 27, 29, 33, 35, and 39: Purl.
• Rows 4 and 34: P3, *k2tog, yo, k3, yo, ssk, p5, repeat from * to last 10 sts, k2tog, yo, k3, yo, ssk, p3.
• Rows 7 and 37: P2, *k2tog, yo, k5, yo, ssk, p3, repeat from * to last 11 sts, k2tog, yo, k5, yo, ssk, p2.
• Rows 10 and 40: P1, *k2tog, yo, k7, yo, ssk, p1, repeat from *.
• Row 13: K2tog, yo, *k9, yo, sl1-k2tog-psso, yo, repeat from * to last 11 sts, k9, yo, ssk.
• Row 16: K1, *yo, ssk, p7, k2tog, yo, k1, repeat from *.
• Row 19: K2, *yo, ssk, p5, k2tog, yo, k3, repeat from * to last 11 sts, yo, ssk, p5, k2tog, yo, k2.
• Row 22: K3, *yo, ssk, p3, k2tog, yo, k5, repeat from * to last 10 sts, yo, ssk, p3, k2tog, yo, k3.
• Row 25: K4, *yo, ssk, p1, k2tog, yo, k7, repeat from * to last 9 sts, yo, ssk, p1, k2tog, yo, k4.
• Row 28: K5, *yo, sl1-k2tog-psso, yo, k9, repeat from * to last 8 sts, yo, sl1-k2tog-psso, yo, k5.