By LEAH WANKUM
Managing Editor

(WARRENSBURG, Mo, digitalBURG) — “Did you see Jimmy Fallon last night?” asked Professor Curtis Cooper on Wednesday. “Supposedly he did a joke on this.”

PHOTO BY BRANDON BOWMAN / PHOTO EDITOR
Curtis Cooper, professor of mathematics and computer science at UCM, manages the GIMIPS software in search of Mersenne prime numbers on 800 of the university’s computers in Warrensburg and Lee’s Summit.

Fallon joked about Cooper’s record Mersenne prime number discovery, saying it would take 25 years to read the 22.3 million digit Mersenne prime number out loud.

“I’d have to calculate it out,” Cooper said after watching “The Tonight Show” clip. “I could do that. I have calculated that if you write it in standard type, like 10 characters per inch, it would go for 35 miles.”

And he did calculate it out. If you read one digit per second, it would take 258 days to read M74207281.

Cooper has gotten a lot of publicity and media attention from his most recent discovery, including the mention on “The Tonight Show.”

Cooper, who teaches mathematics and computer science at UCM, discovered his fourth Mersenne prime number on Saturday, Jan. 9, on one of the university’s computers.

Cooper has approximately 800 computers between the Warrensburg and Summit Center campuses hooked up to the Great Internet Mersenne Prime Search, a software created by George Woltman in 1996. GIMPS celebrates its 20th anniversary this year with its 15th discovery of a Mersenne prime number. Cooper manages the GIMPS data through the server located in his office in W.C. Morris Science Building.

A number is prime when the number can’t be divided by any number except itself and 1. A Mersenne prime number is discovered by the algorithm 2^n-1. Cooper’s fourth Mersenne prime number, 2^74207281-1, has more than 22.3 million digits, nearly 5 million digits larger than the previous record Mersenne prime number, which he also discovered in January 2013.

“It was unbelievable and it was as exciting that time as it was the first time,” Cooper said.

Cooper said one of the computers at the Summit Center found the prime number in September, but the software that normally notifies Woltman, Cooper and system administrators of the Mersenne prime had malfunctioned. The computer took 31 days to run the number in order to determine it as a Mersenne prime.

When Aaron Blosser, a system administrator for GIMPS, came across the number on Thursday, Jan. 7, he said he first looked to see whose computer had submitted the result.

“When I saw it was from one of Curtis’ machines, I immediately realized this could be the real deal,” Blosser said in an email. “We get two or three false positives per year, and they’re usually from users with some sort of configuration error that keeps the program from running properly. Just knowing this came from Curtis Cooper increased my confidence in the result to 90 percent or greater.

“It was pretty exhilarating for me since this was the first prime discovery since I took on the role of managing the Primenet web and database services.”

Blosser said he immediately began a double-check of the number through a supercomputer, which could test it in 36 hours to see if it was a Mersenne prime, and also notified Woltman of the discovery.

“It didn’t actually occur to me at the time that I was the first person to lay eyes on this potentially new and largest prime number,” Blosser said. “It wasn’t until later when I realized that even Curtis Cooper was unaware of his discovery yet that I understood what happened.”

Early Saturday morning, he received the results and notified Cooper and system administrators of Cooper’s discovery. Because his computer found the number nearly four months earlier, Cooper had no record of it on his server.

“I didn’t know the machine that did it, and like I said, we got wiped out on that machine so I have no record of anything,” Cooper said. “On the other three (discoveries), I could go back inside the file when I went to the computer and it said, ‘This is prime,’ but there was nothing like that this time.”

GIMPS administrators used the next week and a half to double-, triple- and quadruple-check the number to make sure it was Mersenne prime. A normal computer like Cooper’s, which was CPU Intel I7-4790, takes several weeks to check a number. The computer began checking the number Aug. 17, 2015, and finished Sept. 17, 31 days later.

Hang Chen, one of Cooper’s colleagues, said he wasn’t surprised when he found out about Cooper’s fourth discovery.

“Sooner or later, he’ll definitely get the next one,” Chen said. “Even now, I still say the same for the next one. Basically speaking, we can do almost this forever, we know there’s no limit, so now we can do it forever.

“But the way he’s working on it and the way our school is supporting this project, it’s definitely going to be a few years. There was one case I think it was twice in a nine-month period of time. It could happen again.”

Cooper’s first two record discoveries were in December 2005 and September 2006.

Because the Mersenne prime numbers are so large, Cooper said no one actually knows how to make use of Mersenne primes yet. Prime numbers between 200 and 300 digits in length are used for encrypting transactions over the Internet. But even though Mersenne primes aren’t useful, mathematicians still work to discover even larger Mersenne primes. Cooper is one of 150,000 volunteers for GIMPS who constantly run numbers on their computers to see if they’re Mersenne primes.

While the Electronic Frontier Foundation awards monetary prizes to those who discover the largest prime numbers, Cooper is not actually in it for the money.

“I’m actually doing it for the thrill of the process, the thrill of the discovery of the number,” he said.

Admittedly, Cooper said the prize money of $3,000 for each Mersenne prime doesn’t pay for the cost of running the computers, but the way he sees it, notoriety and publicity of discovering Mersenne primes makes up for it, at least when they get the university’s name right. One NBC story claimed that Cooper teaches at the University of Central Michigan.

“One thing I would counter on that is the computers, if they’re not working on this, would be sitting idle using some electricity anyway,” Cooper said. “We’re probably using a little bit more with the running of this guy.”

The hunt for even larger Mersenne primes doesn’t stop here. GIMPS is now looking for the 100 million digit Mersenne prime. And all for the love of math.