Since 1898 there was a numbering error on the front page of the New York Times every day and it was discovered by a news assistant named Aaron Donovan in 1999.
The New York Times published in January of 2000:
“On Feb. 6, 1898, it seems, someone preparing the next day’s front page tried to add 1 to the issue number in the upper left corner (14,499) and came up with 15,000. Apparently no one noticed, because the 500-issue error persisted until yesterday (No. 51,753). Today The Times turns back the clock to correct the sequence: this issue is No. 51,254. Thus an article on March 14, 1995, celebrating the arrival of No. 50,000 was 500 days premature. It should have appeared on July 26, 1996.”