xkcd is wonderful (though once in a while I don't get it at all, when it involves too much insider computer knowledge). And speaking of approximations, an MIT alum told me around 1993 that pi seconds ~ 1 nanocentury. --Dan Rich wrote: << Today's XKCD cartoon has a nice collection of approximations. http://xkcd.com/1047/ There's the ancient expression 6 pi^5 for the mass ratio of the proton to the electron, and the more accurate (e^8 - 10)/phi. Robert Munafo & REIS are at least partially responsible.
________________________________________________________________________________________ It goes without saying that .
Yes, there are many like that : 10 attoparsecs = 1 feet 1 mile = log(5)*km exp(Pi)-Pi = 19,9990999... http://xkcd.com/217/ found in the 80's by me, Neil and a certain John H. C. Simon Plouffe Le 26/04/2012 06:07, Dan Asimov a écrit :
xkcd is wonderful (though once in a while I don't get it at all, when it involves too much insider computer knowledge).
And speaking of approximations, an MIT alum told me around 1993 that
pi seconds ~ 1 nanocentury.
--Dan
Rich wrote:
<< Today's XKCD cartoon has a nice collection of approximations.
There's the ancient expression 6 pi^5 for the mass ratio of the proton to the electron, and the more accurate (e^8 - 10)/phi. Robert Munafo& REIS are at least partially responsible. ________________________________________________________________________________________ It goes without saying that .
_______________________________________________ math-fun mailing list math-fun@mailman.xmission.com http://mailman.xmission.com/cgi-bin/mailman/listinfo/math-fun
* Simon Plouffe <simon.plouffe@gmail.com> [Apr 26. 2012 08:37]:
Yes, there are many like that :
10 attoparsecs = 1 feet
1 mile = log(5)*km
exp(Pi)-Pi = 19,9990999...
found in the 80's by me, Neil and a certain John H. C.
Simon Plouffe
[...]
Handwritten inside the book cover of my Bronstein/Semendjajew (likely by end of 1980s or start of 1990s): 20 = e^Pi - Pi + 1 / (1111 + 1 /(11 + 1 /sqrt(2))) - 12.14*10^{-13} (the 1/1111 and 1/11 look Pi-ish in handwriting).
On 2012-04-26, Joerg Arndt <arndt@jjj.de> wrote:
Handwritten inside the book cover of my Bronstein/Semendjajew (likely by end of 1980s or start of 1990s):
20 = e^Pi - Pi + 1 / (1111 + 1 /(11 + 1 /sqrt(2))) - 12.14*10^{-13}
(the 1/1111 and 1/11 look Pi-ish in handwriting).
Joerg, That's a pretty cool one. I think I'll add it to my e^pi - pi entry, see [1]. Is is originally by you or someone else? [1] http://mrob.com/pub/math/numbers-4.html#la19_9990 -- Robert Munafo -- mrob.com Follow me at: gplus.to/mrob - fb.com/mrob27 - twitter.com/mrob_27 - mrob27.wordpress.com - youtube.com/user/mrob143 - rilybot.blogspot.com
* Robert Munafo <mrob27@gmail.com> [Apr 26. 2012 19:49]:
On 2012-04-26, Joerg Arndt <arndt@jjj.de> wrote:
Handwritten inside the book cover of my Bronstein/Semendjajew (likely by end of 1980s or start of 1990s):
20 = e^Pi - Pi + 1 / (1111 + 1 /(11 + 1 /sqrt(2))) - 12.14*10^{-13}
(the 1/1111 and 1/11 look Pi-ish in handwriting).
Joerg,
That's a pretty cool one. I think I'll add it to my e^pi - pi entry, see [1]. Is is originally by you or someone else?
It's by myself. regards, jj
[1] http://mrob.com/pub/math/numbers-4.html#la19_9990
-- Robert Munafo -- mrob.com Follow me at: gplus.to/mrob - fb.com/mrob27 - twitter.com/mrob_27 - mrob27.wordpress.com - youtube.com/user/mrob143 - rilybot.blogspot.com
_______________________________________________ math-fun mailing list math-fun@mailman.xmission.com http://mailman.xmission.com/cgi-bin/mailman/listinfo/math-fun
Yes, and then there was pi^4 + pi^5 = e^6 which was found by me, however, I found it long ago in an email signature on a USENET group. I was impressed, and later mentioned it to Eric Weisstein, and it ended up in MathWorld (Almost Integer) crediting me. From there it went to Wikipedia (Mathematical Coincidence). Does it have a prior history in the literature? On 4/26/2012 1:07 AM, Simon Plouffe wrote:
Yes, there are many like that :
10 attoparsecs = 1 feet
1 mile = log(5)*km
exp(Pi)-Pi = 19,9990999...
found in the 80's by me, Neil and a certain John H. C.
Simon Plouffe
participants (5)
-
Dan Asimov -
David Wilson -
Joerg Arndt -
Robert Munafo -
Simon Plouffe