LAS VEGAS — Preliminary attendance numbers show that 14,564 were registered at the end of the first three days of the four-day Clean Show in Las Vegas, according to Riddle & Associates, the show’s management firm.Attendance at Clean ’07 topped the previous show — Clean ’05 in Orlando, Fla. The attendance number will increase when the final day’s registration is included. Total attendance at Clean ’05 was 13,951.There was 227,950 net square feet of exhibit space, slightly lower than the Orlando square footage of 228,850. Clean ’07 had 484 exhibiting companies.John Riddle, Clean Show manager, emphasized that these are preliminary numbers. Official Clean Show numbers will be announced as soon as they are available, Riddle added.As for the show itself, the exhibitors were generally pleased, and said the show was above average, according to an informal American Coin-Op poll. The educational sessions were also well attended and covered a host of topics such as the future of the industry, ways to improve your bottom line and how to evaluate a coin laundry investment.