Shown with a cast-on count of 3 stitches.  

• Row 1 (RS): K1, kfb, k1 (4 sts).
• Row 2: K4.
• Row 3: Knit to last 2 sts, kfb, k1 (5 sts).
• Row 4: K5.
• Row 5: Knit to last 2 sts, kfb, k1 (6 sts).
• Row 6: K6.
• Row 7: Knit to last 2 sts, kfb, k1 (7 sts).
• Row 8: K7.
• Row 9: Knit to last 2 sts, kfb, k1 (8 sts).
• Row 10: K8.
• Row 11: Knit to last 2 sts, kfb, k1 (9 sts).
• Row 12: K9.
• Row 13: Knit to last 2 sts, kfb, k1 (10 sts).
• Row 14: K10.
• Row 15: Knit to last 2 sts, kfb, k1 (11 sts).
• Row 16: K11.
• Row 17: Knit to last 2 sts, kfb, k1 (12 sts).
• Row 18: K12.
• Row 19: Knit to last 2 sts, kfb, k1 (13 sts).
• Row 20: K13.
• Row 21: Knit to last 2 sts, kfb, k1 (14 sts).
• Row 22: K14.
• Row 23: Knit to last 2 sts, kfb, k1 (15 sts).
• Row 24: K15.
• Row 25: Knit to last 2 sts, kfb, k1 (16 sts).
• Row 26: K16.
• Row 27: Knit to last 2 sts, kfb, k1 (17 sts).
• Row 28: K17.
• Row 29: Knit to last 2 sts, kfb, k1 (18 sts).
• Row 30: K18.
• Row 31: Knit to last 2 sts, kfb, k1 (19 sts).
• Row 32: K19.
• Row 33: Knit to last 2 sts, kfb, k1 (20 sts).
• Row 34: K20.