arduino - How to Cascade 4017 Decade Counters?

I am creating a 16 by 16 LED Matrix using 74hc595 Shift Registers to address the columns and using 4017 Decade Counters to control the row. I am using the 4017's in connection with a transistor to sink the current from the LED's. I understand how to use one 4017 to sink the current but I am trying to cascade another 4017 so I can count until 20 using outputs. I have an arduino providing the clock signal and have tied ENABLE output to ground, and can control CLOCK and RESET

An explanation of why a supposed solution works would also be great, as I would love to understand how my matrix works from the inside out.

Answer

Actually the linked HC4017 data sheet explains how to expand the counter. Look at page 15. But you only get 17 stages out of 2 counters, and additional 8 stages for each additional one.