perl -nle 'print "match" if /^\d(?:\d| (?![^ ])){19}$/'

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Matches 1 digit followed by 19 digits or spaces-not-followed-by-a-non-space.

-sauoq
"My two cents aren't worth a dime.";

In reply to Re: Regex to match 20 chars of some digits followed by some spaces by sauoq
in thread Regex to match 20 chars of some digits followed by some spaces by leriksen

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