[match x amount of times using iterations] #regex

m.sh

# using the {x} will match whatever comes before it x amount of times
echo "12341234444412354444" | grep -P "4{3}" # will match 3 times '444'


# using the {x,y} will match a range from x to y
echo "12341234444344412354444" | grep -P "4{1,4}" # will match 4, 4444, 444, 4444[