Shown with a cast-on count of 2 stitches.  

• Row 1 (RS): K1, yo, k1 (3 sts).
• Rows 2, 4, 8, 10, 14, 16, and 18: Purl.
• Row 3: K1, M1R, k1, M1L, k1 (5 sts).
• Rows 5, 7, 11, and 13: Knit.
• Row 6: P2, M1L, p1, M1R, p2 (7 sts).
• Row 9: K3, M1R, k1, M1L, k3 (9 sts).
• Row 12: P2, p2tog, p1, ssp, p2 (7 sts).
• Row 15: K1, ssk, k1, k2tog, k1 (5 sts).
• Row 17: K1, sl1-k2tog-psso, k1 (3 sts).
• Row 19: Sl1-k2tog-psso (1 st).