[Cryptography] ideas for (long) Nothing up my sleeve numbers

[Jerry Leichter]

On Mar 31, 2014, at 3:09 PM, Bear <bear at sonic.net> wrote:
> If you want "nothing up my sleeve" numbers start with a source that 
> has long been published and do a simple repeatable manipulation to it.  
Exactly backwards.

Instead, compose a message of the following form:  "The constants are computed by taking the closing prices of the following 100 stocks, as published in <pick your publication> on <date in the future>, feed in the order given into the following procedure: ..."  Publicly commit to this message - or, better, to the one-way hash of this message - before the magic date arrives.

There are enough values published that there's always the possibility that you rooted around until you found an appropriate one.  By committing to a value that you could not have known in advance - there's tons of data you can use for this purpose - you eliminate that possibility, which will always be present if you use pre-existing values.
                                                        -- Jerry