If it doesn't and you get another syntax error, try issuing the first command again. If this doesn't solve the problem, you might want to ask for help. Then Maple will treat this as an equation and not an assignment. See the following example. The usual reason for this error is that Maple can't compute numerical values of the expression you asked it to plot.
Maple use square brackets to indicate a list and curly braces to indicate a set.
Some examples are shown below. The Maple seq command has the undesirable side-effect shown in the example below. This is not a problem unless you want to use i as a variable later on in your Maple session, as shown in the example below. The last two commands in the example show how to solve this problem. This is a problem with a printed worksheet having too many page breaks.