There are some counters at the top. Including a .....
At the bottom are some gates made of other gates.
Digital Sequential circuits
RS, JK, D, T
Shift Registers (SISO, SIPO, PISO, PIPO)
Counters (Asynchronous and Synchronous)
Counters with Shift Registers (RING counter, JOHNSON's counter)
The output of the prime number identifier circuit is HIGH for input combinations representing prime numbers, LOW otherwise.
Fig. 8-20 from Malvino
Simulates a 2 party electronic voting system with an added feature of NOTA option for voters.