How to search for text between tabs

Ok, I have searched the other posts in the forum but so far I haven’t found an answer. I have the Alternative Find and Replace extension installed for Writer. My issue is this: I have a 40+ page long document that I’m having to reformat. I’ve been able to use find/replace to do everything except this one function. Any help?

I am wanting to search for a number that is located between two tab stops. I am able to use ^\d{1,134} to search for numbers that are at the beginning of a paragraph, but so far, the only way I’m able to find the numbers that come between the tabs is to search for \t\d{1,134} but that finds the tab also…and I don’t want to find/replace the tab. I just want to replace the digit that comes after the tab. Any suggestions?

With lookbehind and lookahead assertions: (?<=\t)\d{1,134}(?=\t) is the regex of your choice.