Shown with a cast-on count of 16 stitches.  

• Rows 1, 3, 5, 13, 19, 21, 23, 25, 27, 29, 31, 33, 39, 47, 49, and 51 (RS): Knit.
• Rows 2, 4, 48, and 50: Knit.
• Rows 6 and 46: K4, p8, k4.
• Row 7: K4, M1L, k3, M1L, k2, M1R, k3, M1R, k4 (20 sts).
• Rows 8 and 44: K4, p12, k4.
• Row 9: K4, M1L, k5, M1L, k2, M1R, k5, M1R, k4 (24 sts).
• Rows 10 and 42: K4, p16, k4.
• Row 11: K4, M1L, k7, M1L, k2, M1R, k7, M1R, k4 (28 sts).
• Rows 12, 14, 38, and 40: K4, p20, k4.
• Row 15: K4, M1L, k9, M1L, k2, M1R, k9, M1R, k4 (32 sts).
• Rows 16 and 36: K4, p24, k4.
• Row 17: K4, M1L, k11, M1L, k2, M1R, k11, M1R, k4 (36 sts).
• Rows 18, 20, 22, 24, 26, 28, 30, 32, and 34: K4, p28, k4.
• Row 35: K4, k2tog, k9, k2tog, k2, k2tog, k9, k2tog, k4 (32 sts).
• Row 37: K4, k2tog, k7, k2tog, k2, k2tog, k7, k2tog, k4 (28 sts).
• Row 41: K4, k2tog, k5, k2tog, k2, k2tog, k5, k2tog, k4 (24 sts).
• Row 43: K4, k2tog, k3, k2tog, k2, k2tog, k3, k2tog, k4 (20 sts).
• Row 45: K4, k2tog, k1, k2tog, k2, k2tog, k1, k2tog, k4 (16 sts).