This pattern uses Chain, Single Crochet & Double Crochet stitches. It is based on multiples of 7 + 2.
I began this sample on a base of 21 single crochet. Next row begins pattern: Ch-3, dc same space as begin chain 3, chain-2, skip next 5 stitches, 4 double crochet next st, chain 1, double crochet next st.