After reading through Lachenmeyer’s 13: The Story of the World's Most Popular Superstition, I discovered that very few triskaidekaphobes today connect unlucky 13 to the Last Supper, even though this is thought to be the major historical basis for the superstition (Lachenmeyer 132). […] Lachenmeyer gives an example of a typical triskaidekaphobe, a 40-year-old man from Wisconsin who has paranoia regarding Friday the 13ᵗʰ.
Source: wiktionary