Unfortunately, there's no built-in way to do this.
I usually concatenate the Parameter values with JOIN. I use PIPES as the separator in case the text has commas. You also want to add PIPES to the start and end of the string so when you search for 3, it doesn't find 13.
"|" + JOIN(Parameters!RecsIncl.Value, "|") + "|"
|1|2|3|5|8|13|
and then search for the value as a string using the INSTR function. INSTR returns 0 if not found or the position if found.
INSTR( "|" + JOIN(Parameters!RecsIncl.Value, "|") + "|", "|3|") > 0
Your expression would be something like
=IIF(INSTR( "|" + JOIN(Parameters!RecsIncl.Value, "|") + "|", "|3|") > 0, false, true)