Zsbán Ambrus wrote: > On Sun, May 11, 2008 at 3:37 PM, John Randall > <[EMAIL PROTECTED]> wrote: >> Another problem from HAKMEM. >> >> Suppose we start with a number, write it out in words, take the >> length, and keep going. For English, the result will always converge >> to 4 (and, as far as I can tell, to 3 for Chinese). > > Wow, this is in HAKMEM? I never noticed it. I only knew this problem > from the book Csákány Béla: Diszkrét matematikai játékok (Polygon, > Szeged, 1998, page 182). > > Now that I re-read that part of the book, it does indeed credit Gosper > and Schroppel (who are authors of HAKMEM).
ITEM 134 (Schroeppel, Gosper): Let N be iteratively replaced by (FLATSIZE (LONGHAND N)), the number of letters in N written longhand (e.g., 69 -> SIXTY NINE -> 9 (10 counting blanks)). The process invariably loops at 4 = FOUR. See http://www.inwap.com/pdp10/hbaker/hakmem/flows.html Best wishes, John ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
