Zombie process using termux
I just created 100 zombie processes on Termux using:

for n in {1..100}; do (sleep 1 &amp; exec sleep 10) &amp; done


and they do exist for 10 seconds as expected, then reaped by init. To see zombie processes: 

~$ ps axo stat,ppid,pid,cmd | grep ^Z


Or just to take count use grep -c ^Z.