Código :
for(n=0;n<total;n++){
if(["pub_mc"+n]!==clip){
var ["xTween"+n] = new Tween(_level.holder["pub_mc"+n], "_x", mx.transitions.easing.Strong.easeOut,_level.holder["pub_mc"+n]._x,1200, 4, true);
}
} si pongo el nombre de variable así (["xTween"+n]) no funciona 