Tech exec Mike Zisman came up with Golf Genius in January 2008 when the Wayne-based email pioneer was planning a golf trip for himself and seven other guys to Sea Island, Ga.

Crumpled yellow pages littered the bedroom floor as he argued with his wife, Linda Gamble, over foursome combinations.

A light bulb popped for Zisman: scheduling a four-day golf trip for eight guys of differing abilities was a puzzle similar to airlines routing planes to airports or Federal Express delivering packages to homes.

“I can do that,” the Wharton Ph.D. told his wife.

Zisman launched Golf Trip Genius a year later, using a freelance Romanian coder and Amazon servers, with accounting features for tracking per-golfer meal and hotel costs, course fees and side bets.

After explosive growth and wide adoption at thousands of U.S. golf courses, Zisman expects his souped-up app and software version of Golf Genius to schedule 25 million rounds of individual and tournament golf in 42 countries in 2019. It minimizes the number of times that golfers play together and maximizes the times that they play others in groups, along with offering all-important live scoring on smartphones and club leader boards so that weekend and amateur tournament golfers can feel like pros on Fox, NBC or ESPN.

Golf Genius has inked deals with the U.S. Golf Association and the Golf Channel to use the platform, and Zisman has invested several million dollars of his own money into the venture, saying revenues are growing by 30 percent a year. The Philadelphia-area clubs that use it include the Merion Golf Club, Philadelphia Cricket Club and Aronimink Country Club.

Will McIntosh, executive vice president for the Golf Channel, said that the 69-year-old Zisman is an “overnight success eight years in the making.” The Comcast-owned Golf Channel has said it will use Golf Genius for its amateur series with 7,000 competitors and 800 events in 2020.

Gareth Lundt, head of the Golf Handicap Information Network at the United States Golf Association, said “there is no better tournament software out there.” Competitors include 18Birdies, Event-Man Tournament Software, Tournament Expert, VPAR Golf and Golf GameBook.

A college fraternity brother teased Zisman recently, saying “Mike, it’s good to know that for your swan song, you are solving one of the really great problems facing society.”

But the Golf Genius platform is highly scalable, and the math behind it is surprisingly complex.

Marshall Fisher, a professor at the Wharton School, says hard-to-solve computing problems such as the golf buddy scheduling have been knocking around unsolved since the 1970s, known in another variation as the “Traveling Salesman Problem,” or how to calculate the shortest route for a salesman traveling to 100 cities.

“If you had all the computers in the world, you could not get to it,” Fisher said. The best one can do, Fisher said, is to get a “pretty good answer.”

According to Zisman, the number of possible foursome combinations for 16 golfers playing five rounds is 26 followed by 24 zeros.

“To place this in perspective,” Zisman added, “the number of stars in the universe is 10 followed by 21 zeros.”

A Pittsburgh native, Zisman got his doctorate at Wharton in decision sciences, or computer science and operation research. He joined the Massachusetts Institute of Technology faculty in 1977. But he returned to the Philadelphia area after deciding the academic life wasn’t for him to launch Soft-Switch in Wayne, raising $20 million in venture capital.

In the pre-internet era, Soft-Switch broke down the proprietary email walls between big computer makers like Digital Equipment Company, Wang and Hewlett-Packard so that the users of these different computer brands could email each other.

“As the internet came along, we connected corporate email to the internet,” Zisman said.

Zisman sold Soft-Switch with 450 employees to Lotus Development Corp. for $62 million in cash in 1994. IBM bought Lotus a year later for more than $3 billion.

Zisman stayed on at IBM for about a decade, working from his Main Line home. He then faded from public view into a tech-millionaire’s retirement and golf -- or seemed to. He’s still a board member, treasurer and chairman elect of the Kimmel Center, and serves on the boards of Philly tech companies LoanLogics and WizeHive.

He spoke in his home office that Zisman calls “a real garage and intergalactic headquarters” for the globe-straddling Golf Genius. He wrote some of the original software code for Golf Genius himself -- just because it seemed fun. He has retained his original Romanian coder who now runs a 25-person tech team in Romania. Other Golf Genius executives work from their homes and Zisman has hired pros at golf clubs around the United States to pitch the service.

Golf Genius scheduled two million rounds of golf in 2016, eight million rounds in 2017 and 18 million rounds this year. Zisman expects growth to continue due to partnerships with the golf association and cable channel.

On weekends in the summer, Zisman can watch more than 100,000 golfers log on to Golf Genius.

“I said ‘let’s build this on Amazon,’” Zisman said. “First, it was Golf Trip Genius and then Golf League Genius. By then I realized we had a powerful system.”