The number 7 is seen as lucky in slots and pop culture because it has long been...

https://www.kilobookmarks.win/the-number-7-is-seen-as-lucky-in-slots-and-pop-culture-partly-because-classic

The number 7 is seen as lucky in slots and pop culture because it has long been linked to good fortune. Classic slot machines often feature triple 7s, or "777," as a winning combination