Shown with a cast-on count of 70 stitches.  

• Rows 1 and 23 (RS): [P1, k1] 4 times, [p3, k3] 9 times, [p1, k1] 4 times.
• Rows 2 and 24: [P1, k1] 4 times, [p3, k3] 9 times, [p1, k1] 4 times.
• Row 3: [P1, k1] 4 times, [p3, k3] 9 times, turn (62 sts).
• Rows 4 and 20: [P3, k3] 9 times, turn (54 sts).
• Rows 5 and 19: [P3, k3] 8 times, turn (48 sts).
• Rows 6 and 18: [P3, k3] 7 times, turn (42 sts).
• Rows 7 and 17: [P3, k3] 6 times, turn (36 sts).
• Rows 8 and 16: [P3, k3] 5 times, turn (30 sts).
• Rows 9 and 15: [P3, k3] 4 times, turn (24 sts).
• Rows 10 and 14: [P3, k3] 3 times, turn (18 sts).
• Rows 11 and 13: [P3, k3] twice, turn (12 sts).
• Row 12: P3, k3, turn (6 sts).
• Row 21: [P3, k3] 9 times, [p1, k1] 4 times (62 sts).
• Row 22: Knit (70 sts).