Dave Green reports that 'mtve' has solved the Grandfather Problem for Conway Life. GP is to find a pattern with a one-generation predecessor, but no two-generation predecessor. ----- Forwarded message from LifeCA@yahoogroups.com ----- Date: Sat, 7 May 2016 17:52:34 -0500 From: "Dave Greene david.m.greene@gmail.com [LifeCA]" <LifeCA@yahoogroups.com> Subject: [LifeCA] No Grandparents! To: LifeCA <LifeCA@yahoogroups.com> On May 5th, 'mtve' on the conwaylife.com forums solved the grandfather problem, with a 298-cell pattern: x = 24, y = 23, rule = B3/S23 8ob5ob4ob3o$obo2b2o2b3o2b4ob2o2bo$2obob4ob4ob2obo2b3o$3obobobobo2bob3o b3o$ob2o6bo2b5o3b2o$bobob9obobo$obob2o4bo2bob4obo$obobo2b3ob3ob2o$4o2b 2ob3ob4o4bo$4ob6o2bo6bo$obob3ob2ob2ob3ob2o3bo$ob3obob6ob4obo$2b6obob2o 2b3o$2o2bobobob4o$b4ob4o2b6o4b2o$obobobo2b2ob2o2b2o2b3o$o3b2ob2o2b3ob 2o3bo$2ob2o4b2o4b3o$3obob5o3b4obobobo$ob4o2b2o3bobo4bo2bo$2ob2o4b2o3bo 5b2obo$b4obo2bobo4bob2o2b2o$3o3b2ob3o2bobo6bo! The pattern is rumored to have 17,920 parents that all contain the same 622-cell orphan. Matthias Merzenich ran a search in JLS to verify: http://www.conwaylife.com/forums/viewtopic.php?f=2&t=576&p=30713#p30694 Some details on the algorithm used to make the discovery are here: http://www.conwaylife.com/forums/viewtopic.php?f=2&t=576&p=30713#p30667 Is the $50 prize mentioned in LifeLine #6 still available, or was there a statute of limitations that expired sometime in the intervening four decades? Keep the cheer, Dave Posted by: Dave Greene <david.m.greene@gmail.com>