Not the fastest method... f=: -.@:(1&e.)@:(#@:~."1)@(3&(]\))`0:@.(1&e.@:('0456789'&e.))@:": D=: 1e5 + i. 1e6 - 1e5 +/ f"0 D 492 -------------------------------------------- On Mon, 4/9/18, Skip Cave <s...@caveconsulting.com> wrote:
Subject: [Jprogramming] Quora Problem To: "programm...@jsoftware.com" <programm...@jsoftware.com> Date: Monday, April 9, 2018, 2:51 PM Here's a fun math challenge on Quora: Find the number of 6-digit numbers made up of the digits 1, 2, and 3 which have no digit recurring three or more times, consecutively? The link to my answer on Quora is: https://goo.gl/BzBDQe Skip Cave Cave Consulting LLC ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm