Hi,
Try the action wizard included in the attached file or directly this script from the console:
d0=new Date();
starting=util.printd("mm/dd/yy – hh:MM:ss tt",d0);
var addBlankPageAfter=[];
for (var p=0; p<this.numPages-1; p++) {
console.clear();
console.println("Process starting: "+starting);
console.println("Processing the page #"+(p+1)+"/"+this.numPages);
var numWords=this.getPageNumWords(p);
for (var i=0; i<numWords; i++) {
var ckWord=this.getPageNthWord(p, i, true);
if (this.getPageNthWord(p, i, false)=="pag. " && ((this.getPageNthWord(p, i+1, true)=="1" && this.getPageNthWord(p, i+2, true)=="of" && this.getPageNthWord(p, i+3, true)=="1") || (this.getPageNthWord(p, i+1, true)=="3" && this.getPageNthWord(p, i+2, true)=="of" && this.getPageNthWord(p, i+3, true)=="3"))) {
addBlankPageAfter.push(p);
break;
}
}
}
var pageBox=this.getPageBox("Crop",0);
if (addBlankPageAfter.length) {
for (var i=addBlankPageAfter.length-1; i>=0; i--) {
console.clear();
console.println("Process starting: "+starting);
console.println("Adding a blank page after page #"+(addBlankPageAfter[i]+1));
this.newPage(addBlankPageAfter[i]+1, pageBox[2], pageBox[1]);
}
this.saveAs(this.path.replace(/.pdf$/i," & Blank Pages.pdf"));
this.pageNum=0;
this.viewState={overViewMode:2};
var plurial=(addBlankPageAfter.length>1)?"s":"";
var txt=addBlankPageAfter.length+" blank page"+plurial+" added.\r\r";
} else var txt="No page found in this document.\r\r";
df=new Date();
ending=util.printd("mm/dd/yy – hh:MM:ss tt",df);
console.println("\rProcess ending: "+ending);
temps=(df.valueOf()-d0.valueOf())/1000/60;
var theMinutes=parseInt(temps);
var theSeconds=(temps-theMinutes)*60;
var theSeconds=parseInt(theSeconds*10)/10;
var theTime="";
if (theMinutes>0) {
if (theMinutes==1) var theTime="1 minute";
else var theTime=theMinutes+" minutes";
}
if (theSeconds>0) {
if (theSeconds<2) var theTime=theTime+" "+theSeconds+" second";
else var theTime=theTime+" "+theSeconds+" seconds";
}
var theTime=theTime.replace(/^\s+|\s+$/gm,"");
txt+="Process starting: "+starting+"\rProcess ending: "+ending+"\rProcess duration: "+theTime;
console.clear(); console.show();
console.println(txt);
app.alert(txt,3);
Here is the result of a test I did:

@+