Shown with a cast-on count of 45 stitches.  

• Rows 1, 3, 5, 7, 9, 11, 13, 15, 17, and 19 (WS): K4, purl to last 4 sts, k4.
• Row 2: K5, *yo, ssk, k7, k2tog, yo, k1, repeat from * to last 4 sts, k4.
• Row 4: K5, *k1, yo, ssk, k5, k2tog, yo, k2, repeat from * to last 4 sts, k4.
• Row 6: K5, *[yo, ssk] twice, k3, [k2tog, yo] twice, k1, repeat from * to last 4 sts, k4.
• Row 8: K5, *k1, [yo, ssk] twice, k1, [k2tog, yo] twice, k2, repeat from * to last 4 sts, k4.
• Row 10: K5, *[yo, ssk] twice, yo, sl1-k2tog-psso, yo, [k2tog, yo] twice, k1, repeat from * to last 4 sts, k4.
• Row 12: K5, *k3, k2tog, yo, k1, yo, ssk, k4, repeat from * to last 4 sts, k4.
• Row 14: K5, *k2, k2tog, yo, k3, yo, ssk, k3, repeat from * to last 4 sts, k4.
• Row 16: K5, *k1, [k2tog, yo] twice, k1, [yo, ssk] twice, k2, repeat from * to last 4 sts, k4.
• Row 18: K5, *[k2tog, yo] twice, k3, [yo, ssk] twice, k1, repeat from * to last 4 sts, k4.
• Row 20: K4, k2tog, yo, *[k2tog, yo] twice, k1, [yo, ssk] twice, yo, sl1-k2tog-psso, yo, repeat from * to last 15 sts, [k2tog, yo] twice, k1, [yo, ssk] 3 times, k4.