While many of the Nupedia contributors refused to participate in the collaborative experiment, others did. It launched in January 2001, and within days, Wikipedia had published more articles than Nupedia. By the end of January, the site had 600 articles; by March, that number had doubled; in May, it doubled again. By the end of its first year, users had created over 20,000 encyclopedia entries. Thanks to its "radical collaboration," Wikipedia went into hypergrowth mode, while Nupedia was eventually shut down with its original 25 well-researched articles.