Say I want to count sheets 1-31, how would I write this then?

=SUMPRODUCT(COUNTIF(INDIRECT("'"&DEFINEDSHEET&"'!$L$4:$L$8"),"CLIENT"))
tried
=SUMPRODUCT(COUNTIF(INDIRECT("'"&DEFINEDSHEET1:31&"'!$L$4:$L$8"),"CLIENT"))
doesnt work...