Tom Fernsler, a mathematician at the University of Delaware, said 2012's three Friday the 13ths, Jan. 13, April 13 and July 13, are all exactly 13 weeks apart, the first time that has happened since 1984, USA Today reported Friday.
Fernsler said 13 is historically seen as unlucky, as is Friday. He said Jesus was crucified on a Friday and Judas, the apostle who betrayed him, was the 13th guest at the Last Supper.
"If you're not superstitious, maybe you should be," Fernsler said. "Eighty-seven percent of all the people in the world are superstitious about something. The other 13 percent are liars."