Re: [PrimeNumbers] Re: Easily memorized primes
- 911 :)
From: djbroadhurst <d.broadhurst@...>
Sent: Wednesday, September 2, 2009 5:35:20 PM
Subject: [PrimeNumbers] Re: Easily memorized primes
--- In primenumbers@ yahoogroups. com,
"robert44444uk" <robert_smith44@ ...> wrote:
> I think it is a bit sad that 11092001 is a prime.20032003 is a composite number that is hard for me to forget:
> As a UK date it tells a story.
http://tech. groups.yahoo. com/group/ primenumbers/ message/11863
[Non-text portions of this message have been removed]
- Hi , all ,
There may be several different challenges here .
> 10^700+7This is more of an expression than a numeral .
> 11092001 is a prime. As a UK date it tells a story.Yes , but it fails to comply with ISO 8601 , and is hence
obsolete and confusing , just as e-mail dates often are .
I tend to think of this challenge :
One may be called upon to name a large prime at a social
gathering , prototypically a "cocktail party" .
You may know a large prime , but can you say it ?
A long string of digits can be hard to speak and even
harder to understand , so there is a long-standing and
useful protocol :
911 can be spoken "nine hundred eleven"
( tho nine hundred onety-one would make more sense ) .
When I write below "123" , I mean
"one hundred twenty-three" .
123123456456911 is prime and can be said :
123 trillion 123 billion 456 million 456 thousand 911 .
For the more adventurous :
123123456456789789911 is prime and can be said :
123 quintillion 123 quadrillion
456 trillion 456 billion 789 million 789 thousand 911 .
- --- In email@example.com,
"Walter Nissen" <nissen@...> wrote:
> You may know a large prime, but can you say it?..............."eleven sextillion
one hundred and eleven quintillion
one hundred and eleven quadrillion
one hundred and eleven trillion
one hundred and eleven billion
one hundred and eleven million
one hundred and eleven thousand
one hundred and eleven"
can be said without inhaling
- --- In firstname.lastname@example.org, "djbroadhurst" <d.broadhurst@...> wrote:
>David stopped at sex and left us almost breathless. But he knows we can have more, much more, with a lot of air to spare.
> --- In email@example.com,
> "Walter Nissen" <nissen@> wrote:
> > You may know a large prime, but can you say it?
> ..............."eleven sextillion
> one hundred and eleven quintillion
> one hundred and eleven quadrillion
> one hundred and eleven trillion
> one hundred and eleven billion
> one hundred and eleven million
> one hundred and eleven thousand
> one hundred and eleven"
> can be said without inhaling
9 * 10^201 + 1 is prime, otherwise known as the memorable
Nine Sexsexagintillion and One.
If anyone thinks this sounds like
"Sex, sex again 'till yin and one"
you're imagining things. Get back to work!
- Suppose that we parse the string "cab", in base p, as
12*p^2 + 10*p + 11. Then "cab" is a prime in the prime
base p = 41, where it evaluates to the decimal number 20593.
Similarly, we may parse the incantation "abracadabra",
in base p, as 10*p^10 + 11*p^9 + 27*p^8 + 10*p^7 + 12*p^6 + 10*p^5
+ 13*p^4 + 10*p^3 + 11*p^2 + 27*p + 10, which evaluates to the prime
8510432846378191 in the prime base p = 31.
The nonce-word "floccinaucinihilipilification" evaluates to the prime
in the prime base 199. For the meaning, see
Puzzle: Find the smallest prime base in which Aristophanes' dish
is prime, if we use O'Neill's tranliteration in line 1170 of
- On 09/03/2009 02:40 AM, djbroadhurst wrote:
> Suppose that we parse the string "cab", in base p, asSpoiler space follows.
> 12*p^2 + 10*p + 11. Then "cab" is a prime in the prime
> base p = 41, where it evaluates to the decimal number 20593.
> Similarly, we may parse the incantation "abracadabra",
> in base p, as 10*p^10 + 11*p^9 + 27*p^8 + 10*p^7 + 12*p^6 + 10*p^5
> + 13*p^4 + 10*p^3 + 11*p^2 + 27*p + 10, which evaluates to the prime
> 8510432846378191 in the prime base p = 31.
> The nonce-word "floccinaucinihilipilification" evaluates to the prime
> in the prime base 199. For the meaning, see
> Puzzle: Find the smallest prime base in which Aristophanes' dish
> is prime, if we use O'Neill's tranliteration in line 1170 of
Sum in base 41843 is
- --- In firstname.lastname@example.org, Alan Eliasen <eliasen@...>
gave a solution in agreement with [spoiler!]
More ambitiously, one might consider the 1185-letter word
for the Tobacco Mosaic Virus, Dahlemense Strain, at
By my reckoning, this is probably prime in
20 different prime bases less than 10^6.