ls, I heard of the following problem from a friend. Given: f(x) = x - f(f(x-1)) f(0) = 1
I can compute f(1) = 1 - f(f(1-1)) = 1 - f(f(0)) = 1 - f(1) <=> f(1) = 1 - f(1) <=> 2f(1) = 1 <=> f(1) = 1/2. But this does not help much: f(2) = 2 - f(f(2-1)) = 2 - f(f(1)) = 2 - f(1/2). Questions: 1. Do functions f exists on R -> R that are continuous? 2. Can J help him with the question? Could memoization help? Thanks for any help. Jan. Visit Oce at drupa! Register online now: <http://drupa.oce.com> This message and attachment(s) are intended solely for use by the addressee and may contain information that is privileged, confidential or otherwise exempt from disclosure under applicable law. If you are not the intended recipient or agent thereof responsible for delivering this message to the intended recipient, you are hereby notified that any dissemination, distribution or copying of this communication is strictly prohibited. If you have received this communication in error, please notify the sender immediately by telephone and with a 'reply' message. Thank you for your co-operation. ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
