Regular Expressions 101

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/
(?:^|[^\d\n])(1[10]{16,}(?!\d))
/
gm
Non-capturing group
(?:^|[^\d\n])
1st Alternative
^
^ asserts position at start of a line
2nd Alternative
[^\d\n]
Match a single character not present in the list below
[^\d\n]
\d matches a digit (equal to [0-9])
\n matches a line-feed (newline) character (ASCII 10)
1st Capturing Group
(1[10]{16,}(?!\d))
1 matches the character 1 literally (case sensitive)
Match a single character present in the list below
[10]{16,}
{16,} Quantifier — Matches between 16 and unlimited times, as many times as possible, giving back as needed (greedy)
10 matches a single character in the list 10 (case sensitive)
Negative Lookahead
(?!\d)
Assert that the Regex below does not match
\d matches a digit (equal to [0-9])
Global pattern flags
g modifier: global. All matches (don't return after first match)
m modifier: multi line. Causes ^ and $ to match the begin/end of each line (not only begin/end of string)
Your regular expression does not match the subject string.

Regular Expression
No Match

/
/
gm

Test String