People may know, or may not know, but
Futurama has lots and lots of
mathematical secrets embedded in various
episodes. My favourite bit of Futurama
maths concerns a particular number; and
it crops up everywhere. For example, if
you look at the whole registry number of
the Nimbus spaceship it is 1729. The
registry number has to be something so
what's wrong with 1729? Well there's
something all about 1729 because if you
look at Bender's serial number in the
episode 'A Christmas Story' his serial
number is 1729. There's another
episode called 'The Farnsworth Parabox'
I think where fries popping out of
different boxes representing different
universes and one of the boxes he pops
out of is universe number 1729. So
someone in Futurama is obsessed with
1729. The person who's obsessed is a chap
called Ken Keeler, or Dr Ken Keeler
because he has a PhD in applied math, he
went to Harvard, he worked at AT&T Bell
Laboratories, he's published papers in
Discrete Mathematics - he's a heavyweight
mathematician and he's a comedy writer
and he works on Futurama. The reason he
loves 1729 is he's paying tribute to
a great indian mathematician called
Ramanujan; and I know you you've talked
about Ramanujan on other clips but
just briefly I'll tell you the story.
Heroic mathematician from very
impoverished background, really had very
little formal education but was a genius
of a mathematician but had nobody who
could mentor him. So he wrote to lots of
great mathematicians overseas; one day a
letter arrived at the the desk of
G.H. Hardy, the great Cambridge mathematician.
And Hardy looked at this envelope full
of theorems and said, either this is
completely fabricated
or it's complete genius, and it was the
latter. And Hardy immediately invited
Ramanujan to sail over to England and
join him at Trinity College Cambridge.
Hardy was no slouch, Hardy is basically
credited with reinvigorating the whole
of British mathematics, which was in the
doldrums at the time, but Hardy himself
said you know if I did one truly
thing it was to enable Ramanujan to
flourish. And so Ramanujan is in England
and and he's doing very well
intellectually but he's suffering
physically, he doesn't like the diet here,
he's a vegetarian, the weather disagrees
with him; and the next thing we know
within a few years he's in hospital
really quite seriously ill in Putney. And
Hardy visits him in hospital and as the
story goes Hardy gets out his cab, sits
by Ramanujan's bed, being mathematicians
they don't necessarily have the most
gossipy chitchat, and Ramanujan says oh
what was the number of the cab you
arrived it? And Hardy says, oh it wasn't
very interesting it was 1729. Now I
find it interesting the fact that he could
remember the number of a cab, but that's
another story. He says oh it wasn't a
very interesting number.
And Ramanujan says no no quite the
opposite, 1729 is a very interesting number.
Because it is the smallest number that
is the sum of two cubes in two different
ways. 1729, and it equals 10
cubed plus 9 cubed, and it also equals
12 cubed plus 1 cubed. It's rare
for numbers to be the sum of two cubes
in two different ways; and this is the
smallest such number, so it's a special
number. And and Ramanujan, you know, just
had an extraordinary ability with numbers
to be able to spot these patterns out of
thin air. And and for this reason 1729
is called a taxi cab number, and that's
why Keeler embeds it in Futurama as a
way of paying tribute to Ramanujan who
died I think about six months later; he
went back to India still in poor health
and died at a very young age. He just
seems to have dreamt numbers and
imagined numbers and thought about
numbers continually. He did tell the
story that at night one of the goddesses,
one of the Hindu goddesses, would whisper
mathematical secrets into his mind. So
whether it was an immense capacity to do
mental gymnastics on the spot or whether
it was just part of his knowledge of
maths - I guess we don't know. You know,
people who are watching this may know
about Ramanujan because people watching
this may be very fond of mathematics; but
beyond this
little group we're in people have never
heard of Ramanujan - and yet thanks to Ken
Keeler, and thanks to Futurama, there's a
little bit of Ramanujan's legacy gets drip
fed on to primetime TV around the world.
And in fact Keeler's gone one step better
because there's one episode,
I think it's 'Bender's Big Score' where Fry
jumps into a taxicab and the number on
the taxi cab is - let me just write this down -
87 - or a 87 million - five
hundred thirty nine thousand, three
hundred and nineteen, okay? That's a
taxicab number in a literal sense, it is
the number of the taxicab, but it's also
a taxicab number in the Ramanujan sense
because it is the smallest number that
is the sum of two cubes in three
different ways. So it equals 167 cubed
plus 436 cubed. It's also
equal to 228 cubed plus 423
cubed; and it's also equal to
255 cubed plus 414 cubed. So
we can call that a taxicab number of
rank three, to call it with
a very very bad pun. And and you might
want to go away and think about what is
the taxicab number of rank four? As far
as I know it's never appeared in
Futurama but it may well do one day so
it'll be a way of spotting it. - (Brady: Simon,)
(you kind of alluded to the fact that by)
(doing this the writer has raised an)
(awareness to a possibly different)
(audience about Ramanujan; do you think)
(that? I mean has he raised awareness? Or is)
(is it is it a hidden knowledge to some extent?)
I mean I think if you've never heard of
Ramanujan, and you're not into
mathematics,
these numbers are arbitrary and and you
won't you won't you won't pick up on it.
But I still think it's a tribute, I think
it's very personal tribute from from
Keeler. It's also him just having a bit of
fun, it's an in-joke.
I think Futurama viewers are probably a
quite a- a surprisingly high
proportion of them will be interested in
mathematics and will pick up on that
reference. I remember one of the writers
said that there was occasionally a bit
of a dispute over mathematics in
Futurama. There's a line where there's a
holographic image involving- I think
Kif says are a million lines of BASIC
there. And they were sat around the table
in the writers room and they said okay,
who knows about BASIC? You know, our viewers
are never going to get that joke. And one
of the lead writers at the time said, it
just doesn't matter. If they don't get it
they don't get it but those people who
know about maths, who know about computer
science, who know about some of the
languages of computer science - they'll
get it. And it'll be a bit of fun for
them. - (Do you ever do it yourself?)
(Do you ever drop things into the things)
(you produce with hidden things that)
(aren't obvious to your viewers or)
(readers? Or is that not the style of a)
(journalist?) - No no um there are some
references in my latest book which those
who know them will spot them and those
who don't won't. And those who don't won't have
their fun spoiled. But there are
references to a certain legal case that
people may spot, but there we go.
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reading or listening that one, very geeky.