For some reason the desmos engine doesn't do mod(x,3)=0, perhaps it's graphing an infinately small point. If you allow the value of the modular function to be less than a small number, say, mod(x,3)<0.01, then you will see the points you expect.
Verbatim is defined as an exact repetition without changing the words. An example of verbatim is when you quote someone exactly without changing anything. word for word; in exactly the same words. Origin of verbatim.
A direct quotation is a report of the exact words of an author or speaker. Unlike an indirect quotation, a direct quotation is placed inside quotation marks. Direct quotations are commonly introduced by a signal phrase (also called a quotative frame), such as Dr. King said or Abigail Adams wrote.