# [RC5] Filling the gaps

Brian Lintz lintbri at charlie.cns.iit.edu
Thu Nov 26 16:10:10 EST 1998

```On Wed, 25 Nov 1998, Ian Samuel wrote:
> Well, no. :)
>
> 56-bit DES contains 72,057,594,037,927,936 possible keys. One 2^30
> keyblock of keys is only 1,073,741,824: less than 0.0000002% of the
> keyspace. The chances of that one block containing the key are, as
> you can see, low.

*smiles*  That's very true... but the same chances lie atop every block :)

There's 8,835,488,640 different tickets I could buy for the Illinois
Lotto...  Each one has a 1-in-8bil chance of winning, yet, in order to
win, that specific ticket has to be played.  Numbers-wise, one block has
1/6 the chance of being the "right" one as a single lottery ticket...
but...  people do win the lotto with just one, and if 8,835,488,640
tickets were sold, and 1 wasn't, all those people lose.  (well, sortof,
they do win if they only got 5 numbers, but they don't win the big
prize - which is the only one available to d.net :) )

Statistically, it doesn't really matter ... each block has the same chance
of winning as the one before it, but it seems like you have less of a
chance winning lotto buying the tickets in order, starting at 1,2,3,4,5,6,
1,2,3,4,5,6,7, all the way up through 43,44,45,46,47,48; than you would
with a more random stab at the possibilities.

My vote, if we ever voted, would be to stripe through it like this:

-     -     -     -     -     -     -     -     -     -
--    --    --    --    --    --    --    --    --    --
---   ---   ---   ---   ---   ---   ---   ---   ---   ---
----  ----  ----  ----  ----  ----  ----  ----  ----  ----
----- ----- ----- ----- ----- ----- ----- ----- ----- -----
------------------------------------------------------------

Just seems like our "lotto" chances of winning are better that way, even
if the mathmatical chances are identical... :)

--Brian

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