Licesense windows server under Hyper-V

I have one psychical server , so I will install Windows Server 2016 Stranded edition .

then I will enable Hyper-V and having 2 VMs Windows Server 2016 Stranded edition

So here I will have 3 OS , but the Vms will be working on the resourse of the host 

The host Will have 16 cores . so each VM will have only 4 cores from the host .

Now, The question is : How many licensee do I need ?

only one for the host with 16 cores or three with 16 cores ?