Received a call. Did not pick up. I'm in the Midwest, United States. Based on reports I'm reading in this block, I'm guessing that this is a computer that is searching/seeking out numbers.
If you have a smart phone, here's what I suggest you do...
1) In your Contacts/Address Book, create a Contact with the name "DO NOT CALL" or "DO NOT ANSWER"
2) Every time an unrecognized number calls you, DON'T ANSWER--let it ring through, and then Google the number and see what sites like this, and others, say about the number.
3) If suspicious, add the number to your "DO NOT CALL" contact. On more recent phones running Android, for example... a single contact can have 20, 25, even 30 different phone numbers associated with them!
4) If your phone won't let you add any more numbers to your contact, start another contact... call it "DO NOT CALL2"... and then "DO NOT CALL3"... etc.
You'd be surprised how many of these numbers cycle around. A lot of telemarketers and scam artists use the same numbers over and over again. Florida, in particular, is a hotbed of criminal activity, especially the fraudulent telemarketer type.