Use a circular needle or a pair of double-pointed needles. Slide after working odd-numbered rows with color A. Turn after working even-numbered rows with color B.
Rows 1, 5, 9, and 13 (WS): P1, *brSl, p1, repeat from *.
Row 2 (WS): Sl1 wyif, k1, *[brSl, k1] 3 times, [brSl, (k1, yo, k1) in next st] twice, [brSl, k1] 3 times, repeat from * to last 3 sts, brSl, k1, sl1 wyif (multiple of 20 sts, plus 5).
Rows 3 and 7: K1, brSl, k1, *brSl, sl1-k2tog-psso, [brSl, k1] 5 times, brSl, k3tog, brSl, k1, repeat from * to last 2 sts, brSl, k1 (multiple of 16 sts, plus 5).
Rows 4, 8, 12, and 16 (RS): Sl1 wyib, p1, *brSl, p1, repeat from * to last st, sl1 wyib.
Row 6 (WS): Sl1 wyif, k1, *[[brSl, k1] twice, brSl, (k1, yo, k1) in next st] twice, [brSl, k1] twice, repeat from * to last 3 sts, brSl, k1, sl1 wyif (multiple of 20 sts, plus 5).
Row 10 (WS): Sl1 wyif, k1, *brSl, (k1, yo, k1) in next st, [brSl, k1] 6 times, brSl, (k1, yo, k1) in next st, repeat from * to last 3 sts, brSl, k1, sl1 wyif (multiple of 20 sts, plus 5).
Rows 11 and 15: K1, brSl, k1, *[brSl, k1] twice, brSl, k3tog, brSl, k1, brSl, sl1-k2tog-psso, [brSl, k1] twice, brSl, k1, repeat from * to last 2 sts, brSl, k1 (multiple of 16 sts, plus 5).
Row 14 (WS): Sl1 wyif, k1, *brSl, k1, brSl, (k1, yo, k1) in next st, [brSl, k1] 4 times, brSl, (k1, yo, k1) in next st, brSl, k1, repeat from * to last 3 sts, brSl, k1, sl1 wyif (multiple of 20 sts, plus 5).