This is a 2-D math parser error. It occurs when an incorrectly formed expression sequence is given.

Tip: If an expression is executed accidentally, it can lead to error messages (if it is not valid Maple syntax). If this happens, toggling the expression to nonexecutable math removes the error message and changes the math to nonexecutable. To change an expression to nonexecutable math use the shortcut key Shift + F5.  For more information, see Executable and Nonexecutable Math.

This example uses incorrect syntax for a sequence.

Solution:

To fix this error, use the correct syntax for a sequence. Sequences are commonly used in Maple in function calls, lists, sets, and subscripts.