Your bug report

#15770: zgrep -n does not work for n>9

which was filed against the gzip package, has been closed.

The explanation is attached below, along with your original report.
If you require more details, please reply to 15770@debbugs.gnu.org.

-- 
15770: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=15770
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