regex - Backreferencing something without putting it in the rest of the expression -

regex - Backreferencing something without putting it in the rest of the expression -

i trying create regular look match words have letter repeats @ to the lowest degree arbitrary number of times.

for example, if want match words have letter repeats @ to the lowest degree 3 times, want match words like

applepie banana insidious

i want able alter number of repeats i'm looking changing 1 number in expression, expressions work number of repeats not i'm looking for.

currently, i'm using

^(?=.*(.))(?=(.*\1){4}).*$

where 4 number of repeats, number can alter whatever number of repeats i'm looking for.

the above regular look appears work, using lookahead can utilize capturing grouping seems unwieldy, , i'm looking improve way solve problem.

this eliminate 1 lookahead:

\b(?=\w*(\w)(\w*\1){2})\w*

start of word, number of word-characters such consist of number of word characters, particular word character, , number of characters , character again, repeated @ to the lowest degree twice.

for 4 repetitions, utilize {3} (for n repetitions, utilize 1 less).

also, sense free replace \b... ^...$ doing if meant match whole lines , not words in text.

regex pcre