Line puffer

A line puffer is a puffer which produces its output by means of an orthogonal line of cells perpendicular to the direction of travel. The archetypal line puffer was found by Alan Hensel in March 1994, based on a spaceship found earlier that month by Hartmut Holzwart. The following month Holzwart found a way to make extensible c/2 line puffers, and Hensel found a much smaller stabilization the following day. But in October 1995 Tim Coe discovered that for large widths these were often unstable, although typically lasting millions of generations. In May 1996, however, Coe found a way to fix the instability. The resulting puffers appear to be completely stable and to exhibit an exponential increase in period as a function of width, although neither of these things has been proved.

Line puffers have enabled the construction of various difficult periods for c/2 spaceships and puffers, including occasionally periods which are not multiples of 4 and which would therefore be impossible to attain with the usual type of construction based on standard spaceships. (See frothing puffer for another method of constructing such periods.) In particular, the first c/2 rake with period not divisible by 4 was achieved in January 2000 when David Bell constructed a p42 forward rake by means of line puffers.

x = 156, y = 32, rule = B3/S23 34b3o27b3o13b3o27b3o$33bo3bo25bo3bo11bo3bo25bo3bo$32b2o4bo11bo11bo4b2o 9b2o4bo11bo11bo4b2o$31bobob2ob2o3b4ob2ob2ob4o3b2ob2obobo7bobob2ob2o3b 4ob2ob2ob4o3b2ob2obobo$30b2obo4bob2ob4o7b4ob2obo4bob2o5b2obo4bob2ob4o 7b4ob2obo4bob2o$29bo4bo3bo4bo2b2obobob2o2bo4bo3bo4bo3bo4bo3bo4bo2b2obo bob2o2bo4bo3bo4bo$6bo17bo16bo4bo7bo4bo27bo4bo7bo4bo25bo17bo$5b3o15b3o 3b2o7b2o6bo7bo6b2o7b2o3b2o7b2o6bo7bo6b2o7b2o12b3o15b3o$3b2ob3o13b3ob2o 100b2ob3o13b3ob2o$4bo2bob2o4bo4b2obo2bo18b2o7b2o35b2o7b2o27bo2bob2o4bo 4b2obo2bo$b2obo4bobob2ob2obobo4bob2o17bo5bo39bo5bo26b2obo4bobob2ob2obo bo4bob2o$b2obobo2bobo7bobo2bobob2o15bo2bo3bo2bo35bo2bo3bo2bo24b2obobo 2bobo7bobo2bobob2o$bo8b3obobob3o8bo16bo2bobo2bo37bo2bobo2bo25bo8b3obob ob3o8bo$2o7b2o9b2o7b3obo15bobo43bobo24bob3o7b2o9b2o7b2o$33b2o12bobobob o39bobobobo21b2o$31b2obo11b2obobob2o37b2obobob2o20bob2o$34b2o9bo3bobo 3bo35bo3bobo3bo18b2o$33bo88bo$35b3o7b2ob2ob2ob2o35b2ob2ob2ob2o16b3o$7b 3o15b3o9b2o78b2o9b3o15b3o$6bo3bo13bo3bo9bo7bo3bo3bo37bo3bo3bo16bo9bo3b o13bo3bo$5b2o4bo11bo4b2o8b2o6bo3bo3bo7b3o9b3o9b3o3bo3bo3bo4b3o8b2o8b2o 4bo11bo4b2o$4bobob2ob2o3b3o3b2ob2obobo8bo21bo3bo7bo3bo7bo3bo14bo3bo7bo 8bobob2ob2o3b3o3b2ob2obobo$3b2obo4bob2ob3ob2obo4bob2o6bobo5b2o5b2o5b2o 3b2o5b2o3b2o5b2o3b2o5b2o5b2o3b2o5bobo6b2obo4bob2ob3ob2obo4bob2o$2bo4bo 3bo4bobo4bo3bo4bo6b3o3b4o3b4o3b2obobob2o3b2obobob2o3b2obobob2o3b4o3b2o bobob2o3b3o6bo4bo3bo4bobo4bo3bo4bo$14bo5bo20b2ob2o2b2ob2o2b2ob2ob2ob2o b2ob2ob2ob2ob2ob2ob2ob2ob2ob2o2b2ob2ob2ob2ob2ob2o20bo5bo$2b2o7b2o9b2o 7b2ob3o5bobo4bobo4bobo3bobo3bobo3bobo3bobo3bobo3bobo4bobo3bobo3bobo5b 3ob2o7b2o9b2o7b2o$36bo82bo$34bo6b2ob2o2b2ob2o2b2ob2ob2ob2ob2ob2ob2ob2o b2ob2ob2ob2ob2ob2o2b2ob2ob2ob2ob2ob2o6bo$34bob2o80b2obo$39b78o$38bo78b o! #C [[ THUMBSIZE 2 THEME 6 GRID GRIDMAJOR 0 SUPPRESS THUMBLAUNCH ]] #C [[ THUMBSIZE 2 ZOOM 6 WIDTH 1000 ]]

Superstable line puffer of width 76 constructed by Tim Coe in 1996 (click above to open LifeViewer) RLE: here Plaintext: here

x = 227, y = 108, rule = B3/S23 113bobo$112bo2bo$111b2o$110bo$69bobo37b4o$68bo2bo36bo4bo$67b2o39bo2bo$ 66bo41bo2bo$65b6obo36bo$53bobo6b2o7b2o37b4obo$52bo2bo5bo3b3ob2o40bo3bo $51b2o7bo3bo4b2o41bo$50bo4bo4bo5bo3b2o40bobo$49b5obo4b3o3b4obo$46b2o 63b3o$45bo3b3o8b3o3b4obo39b2o$44bo3bo11bo5bo3b2o39b3o$44bo5bo9bo3bo4b 2o49bo$44b3o3bo10bo3b3ob2o41bobo2b2obo$45bo4b2obo8b2o7b2obo7bo28bo2bo 2bo$45b2o6bobo9b6obobo6bobo27bo5bo9bo$45bobo8bo9bo7bobobob2obo27bo3bo 8b2obo$45b2o2bo4bo12b4obo3b2o2bo31bo3b3o5bo$46bobo4b3o11bo3b2obobobob 2obo29b2o9bo$52b2o15b2o3bo6bobo32b5obo$46b2o3b2o16b4obo7bo34bo4bo$46bo 2bo2bo4bo14b4o42b2o5bo$47bo3b2ob4o17bo43bo2bobo2bo$47b5o2bobo63bobo3b 2o$48bo3bo3bo67b3o$48bo7b2o66b3o2bo$48bo7b2o25b3o41b2o$49bo2b2o2b2o28b o40bobo$50b4o2bo25bo3bo44bo$56b3o5b2o15b2obo2bo42b3o$50b4o2bo7b3o19bob o18bob2o18b2ob2o$49bo2b2o2b2o8b3o9bob2o4bobo16bobo22b2o7bo$48bo7b2o8bo 2bo8b2o7b2o2b2o11bo5bo19b2o6bo2bo$48bo3b2o2b5o5bo2bo9bo11b2o12b4obo19b 2o5bo3bo$47bob5o2b2o8bo2bo60bobo4bob2obo$46b3o7b2o47bobobo7b2o11b2o5b 2o3bo$47bob5o2bo7bo13b2o24bo2b3o6bob2o11bo6b5o$48bo3b2o2b3o5bo12bo2bo 8bo14bobobo7b2ob2o18b2obobo$48bo7bo7bo12bobo8b3o6b2o6b3o8b2ob3o22b3o 13b2o19b2o$49bo2b2o2b2o20bo8b2obo5bobo7bo10bo2bo23bobo13b2o19b2o20b2o$ 50b4o2b2o10bo18bo9bo20b2o25bo56bo2bo$56b9o3bo16b3o115bob3o$50b4o2b2o 10bo18bo9bo20b2o25bo58b5o$49bo2b2o2b2o20bo8b2obo5bobo7bo10bo2bo23bobo 13b2o19b2o26bo$48bo7bo7bo12bobo8b3o6b2o6b3o8b2ob3o22b3o13b2o19b2o24b2o $48bo3b2o2b3o5bo12bo2bo8bo14bobobo7b2ob2o18b2obobo62bo$47bob5o2bo7bo 13b2o24bo2b3o6bob2o11bo6b5o81b2o$46b3o7b2o47bobobo7b2o11b2o5b2o3bo81bo bo$47bob5o2b2o8bo2bo60bobo4bob2obo81bo$48bo3b2o2b5o5bo2bo9bo11b2o12b4o bo19b2o5bo3bo$48bo7b2o8bo2bo8b2o7b2o2b2o11bo5bo19b2o6bo2bo33b2obo$49bo 2b2o2b2o8b3o9bob2o4bobo16bobo22b2o7bo34bob2obo$50b4o2bo7b3o19bobo18bob 2o18b2ob2o41bobobo13b3o14bobo$56b3o5b2o15b2obo2bo42b3o45bo14bo15bo2bob 2obo$50b4o2bo25bo3bo36bo7bo43bobo16bo13b2o7b2o$49bo2b2o2b2o28bo33b4o 31b2o17b2o31bo4bo$48bo7b2o25b3o31b4obo7b2o21b2obo17b2o30b5obo4b2o$48bo 7b2o59b2o3bo5bo24b2o14b2ob2o31bo8b2obo$48bo3bo3bo58bo3b2obobobobob2o 21b2obo11b6o3bo27bobob2obo$47b5o2bobo58b4obo3b2obo27b3o10bo2b2ob2obo 26bo3bo3bo$47bo3b2ob4o17bo38bo7bobobobob2o18b3o4bo10b2o5bobo26b3o2bo$ 46bo2bo2bo4bo14b4o37b6obobo5bo27b3o10b2o39b4o$46b2o3b2o16b4obo7bo27b2o 7b2obo7b2o24b2o11b2o31bob3o$52b2o15b2o3bo6bobo25bo3b3ob2o36b2o44b2o2b 2o5b4o$46bobo4b3o11bo3b2obobobob2obo24bo3bo4b2o36bo45bobo8bo$45b2o2bo 4bo12b4obo3b2o2bo27bo5bo3b2o81b2o8bo2bo$45bobo8bo9bo7bobobob2obo24b3o 3b4obo32b2o47bo9b2o6bo$45b2o6bobo9b6obobo6bobo116b3o14b3o$45bo4b2obo8b 2o7b2obo7bo25b3o3b4obo80bo2bo7bobo2b2o$44b3o3bo10bo3b3ob2o37bo5bo3b2o 79bo2bo7b2o4bo$44bo5bo9bo3bo4b2o37bo3bo4b2o40bo39b2o6bo3b2o5bo$44bo3bo 11bo5bo3b2o37bo3b3ob2o38bobobo43b3o4b6o$45bo3b3o8b3o3b4obo38b2o7b2o35b o3bo38bobo2b2o7bobo$46b2o65b6obo34b2o41b2o4bo11b4obo$49b5obo4b3o3b4obo 42bo38bo2bo2bo39b2o5bo9bo3b2o$50bo4bo4bo5bo3b2o43b2o33b4obobobo40b6o 12b2o$51b2o7bo3bo4b2o45bo2bo30b2o3bo45bobo14b4o$52bo2bo5bo3b3ob2o46bob o28bo3b2o50b4obo11bo$53bobo6b2o7b2o75b4obobo48bo3b2o$65b6obo72bobo7bo 50b2o$66bo77b6o5b2o49b4o$67b2o74b2o5bo5b3o50bo$68bo2bo70b3o3bo9bo$69bo bo71b3o2b2o$145bo3b3o$143bo7bo$143bobo$142bo$143bobo$143bo$145bo$143b 3o$142bo2b2o$142b3obo$141bo$140b3o$139b3o2bo$140bo$141b4o$141bo$143b2o $143b4o$146bo! #C [[ THUMBSIZE 2 THEME 6 GRID GRIDMAJOR 0 SUPPRESS THUMBLAUNCH ]] #C [[ THUMBSIZE 2 ZOOM 4 WIDTH 1000 HEIGHT 500 ]]

p42 forward rake constructed by David Bell by means of a line puffer in 2000 (click above to open LifeViewer) RLE: here Plaintext: here

See also

• Extensible lineship

External links

• Line puffer at the Life Lexicon
• Line Puffers at Paul Callahan's Page of Conway's Life Miscellany