i need some help with changing this pattern

This is the normal pattern I use for hats:

chain four, double crochet into furthest chain from hook 16 times, join

chain three, double crochet twice into each stitch around, join

chain three, xdouble crochet twice in one stitch, then one dc in nextx repeat xx until end, join

chain three, x2dc in one stitch, then dc once in the next two stichesx repeat xx until end, join

chain three, x2dc in one stitch, then dc once in the next three stichesx repeat xx until end, join

The rest of the hat will be a tube so chain three, and dc each stitch til end, and join. do that for each round until its as long as you want.

I'm trying to change all the double crochets to single crochets, I'm trying to think about how I could do this, anyone have any ideas?