Received repeated calls from 201-636-5744 and 201-636-5788 with no one on the line -- just a single short beep.  I am wondering how to get this to stop.

Do consider maybe getting a call blocking device or phone.. You can google them and many are around $60.00 or so.

Report your callers here, not just to the DNC alone:

https://www.ftccomplaintassistant.gov/#&panel1-1
https://esupport.fcc.gov/ccmsforms/form1088.action
https://complaints.donotcall.gov/complaint/complaintcheck.aspx?panel=2

By State DNC lists:
http://800notes.com/res/DoNotCall.aspx

FCC Abandoned Calls Complaint form:
http://www.fcc.gov/cgb/consumerfacts/1088D-R.pdf
email:  fccinfo@fcc.gov

I'm getting this calls as well.

It is a fax machine and it is so annoying.  I have gotten at least 20 calls in the last 2 hours.  Called NYU Medical Center - the name on the caller ID and they say there isnothing they can do. Ridiculous!