I realized that “Mensa” didn’t contain enough numerals to be a phone number, and knew it must be understood that any future member would be able to figure out the next two digits in the sequence. I tried dialling MENSANE, MENSAIL, MENSAFE, and MENSAAB, but got three rebuffs and a fax tone.
From “How I Joined MENSA” by Steve Martin
If MENSA tests you and says you’re a genius, you might be a genius.
If you join MENSA then you aren’t as smart as they say you are.