The twins' last name is Winklevoss (not Winklevos). —Dan ----- Indeed. Or 'Winklevoses', since it derives etymologically not from the Greek 'Winklevos', but is instead a back-formation from the English word 'Winklevology': https://mathoverflow.net/a/60915/39521 -- APG.

Sent: Friday, May 05, 2017 at 6:25 PM From: "Gareth McCaughan" <gareth.mccaughan@pobox.com> To: math-fun@mailman.xmission.com Subject: Re: [math-fun] Brain teaser

On 05/05/2017 12:20, Veit Elser wrote:

...

One of my favorite moments in “The Social Network” was when the Zuckerberg character refers to the Harvard twins as “the Winklevii”.

It ought to be "Winklevoi", though.