Shown with a cast-on count of 26 stitches.  

• Row 1 (RS): K1, *k2tog, k9, ctr dbl inc, repeat from * to last st, k1 (multiple of 13 sts, plus 2).
• Rows 2, 4, 6, 8, and 10: K1, *p11, p2tog, repeat from * to last st, k1 (multiple of 12 sts, plus 2).
• Row 3: K1, *k2tog, k7, ctr dbl inc, k2, repeat from * to last st, k1 (multiple of 13 sts, plus 2).
• Row 5: K1, *k2tog, k5, ctr dbl inc, k4, repeat from * to last st, k1 (multiple of 13 sts, plus 2).
• Row 7: K1, *k2tog, k3, ctr dbl inc, k6, repeat from * to last st, k1 (multiple of 13 sts, plus 2).
• Row 9: K1, *k2tog, k1, ctr dbl inc, k8, repeat from * to last st, k1 (multiple of 13 sts, plus 2).
• Row 11: K1, *ctr dbl inc, k9, ssk, repeat from * to last st, k1 (multiple of 13 sts, plus 2).
• Rows 12, 14, 16, 18, and 20: K1, *ssp, p11, repeat from * to last st, k1 (multiple of 12 sts, plus 2).
• Row 13: K1, *k2, ctr dbl inc, k7, ssk, repeat from * to last st, k1 (multiple of 13 sts, plus 2).
• Row 15: K1, *k4, ctr dbl inc, k5, ssk, repeat from * to last st, k1 (multiple of 13 sts, plus 2).
• Row 17: K1, *k6, ctr dbl inc, k3, ssk, repeat from * to last st, k1 (multiple of 13 sts, plus 2).
• Row 19: K1, *k8, ctr dbl inc, k1, ssk, repeat from * to last st, k1 (multiple of 13 sts, plus 2).