OCA:Day & Night

Day & Night
x=64, y = 64, rule = B3678/S34678 ! #C [[ THEME Inverse ]] #C [[ RANDOMIZE2 THUMBLAUNCH THUMBNAIL THUMBSIZE 2 GRID ZOOM 6 WIDTH 600 HEIGHT 600 LABEL 90 -20 2 "#G" AUTOSTART PAUSE 2 GPS 8 LOOP 256 ]] LifeViewer-generated pseudorandom soup
View static image
Rulestring	34678/3678 B3678/S34678
Rule integer	242120
Character	Chaotic
Black/white reversal	B3678/S34678
Strobing dual	B01245/S0125
Checkerboard dual	B1e2cn3acjkr4cny5einqy6ei7c/S01e2-ei3acjkr4-ejr5einqy6-cn7c8

Day & Night is a Life-like cellular automaton in which cells survive from one generation to the next if they have 3, 4, 6, 7, or 8 neighbours, and are born if they have 3, 6, 7, or 8 neighbours.

Day & Night is the most well-known self-complementary rule; that is, if all grid cells have their on/off state exchanged, the history of the pattern is the same as the history of the original.

Nathan Thompson explored the rule starting in April 1997, and David Bell discussed the rule in detail the following November.

The rule is rich in spaceships, puffers, and oscillators.

On August 14, 2020, Peter Naszvadi constructed a Rule 110 unit cell in Day & Night, proving the rule Turing-complete.

Behavior

Soups and large unstable patterns in Day & Night tend to evolve into large blobby "islands" with active, "frothy" exteriors and almost completely filled interiors, save for some photonegative oscillators and still lifes. These areas slowly shrink and degenerate, larger ones taking longer, leaking out patterns from their exteriors. Unusual spewing behavior can be observed as well, almost resembling failed spaceships or puffers.

Most of these islands will disappear completely, the resulting ash being much less dense than ash in Conway's Game of Life. However, some can stabilize into large still lifes or trivial oscillators. Escaping spaceships are rare, though some might form from small active areas that shrink into their predecessors.

x = 64, y = 64, rule = B3678/S34678 2bob2ob4o3bo2b4o5b2obob4obo2bo5b2ob5o5b6o$obobo3b2obo2b4o5bobobo3bobo bo4b2ob2o2b3ob5obobobobo$o2bo3b2o3b5o4bo5bo7bobob2ob4o4bob2obobo2bo2b o$2o2b3ob2obobob2obo2bo4b4o2bo3b2obo7b3o11b2o$4bo3bo2b4o3bobo5b4o6bob o2bo3bo2bob2ob2o3bobobo$bo2b2o5b3obobo2bo2bob4obo2b3obo2b3o4b7o3b2ob2o $b2o2bo2bo6bo2b2o3bob3ob2o3bobo5bo3bobobob2ob9o$2o4b2ob6obobo2bob3obo 3bo3b5obo2bobobob2ob5o2bob2o$b3obob2obobo4bob4ob2o5bobobob2o2b6o2bo3b 4obo2bobo$b2o2bo2b2ob2o3b2obobo3b2obo2b2o3bob3o3b7ob2o4bobobo$b3o2bob 2o7bo2bo7b2ob2o3bo2b2ob4obo3bo4b5ob2o$4o2bobo2b2obob2o2bob2o4bo2b5ob2o b2o4bob2o2b2obob7o$bo4bo2b2obob2o2bo2b3o2bo3b3o5bo2bo3bobobo7bobo2bo$ 3bo3bob2obobob2obob2o3b3o2bob4o2bo3bobo5b2o3bo2b2o$4b3obo3bo2bobob4ob 4o2bobobo3bo4b2o3bobo4b3o2b3o$2o8b3obo3bo2b2ob2o2b2obobo5bo5b4o3b3o5b 3o$b2o2b3o2bobo3bo2bo4b2ob3o2b4obo3b3o7bo2bo2bobobobo$2ob2o4b2obo7bob 5obo3b2ob2ob3o2b2ob4o5bob2obobo$2ob8o4bo2bo4bo5bob3o9bob2obob6o3b2o2b o$ob2ob2o7bobobo2b2obo3bo4bo2bo4bo2bobob2o4b2o3bob3o$bobo2b4o2b4o2bob o4bo3b2o2b4ob3o3b5o2bob2o4bob2o$2ob2o3bo2b2ob2obo2b2obob2o2bo6b2o2b3o b5obob2o2b3ob4o$2bobo2bo3b3obo2bo2b3obo3bobo2bob2ob3obo2b2obobobobob3o bobo$2bo2b4o2b2ob4ob5ob3ob3obobo2bo3b5o2b2o3bo2b2obobo$3o2b7o3b6ob4o2b obob2obob3o2b2o2bobobo2b3o2b2obobo$obob5o3b2obob7ob4obob2obo2b3o4bob2o 3b2o4bobobo$o3b2ob2obob2o2b2ob3o5bob2o2b2ob3o3b5ob2o5b2obobobo$3bob6o b5o2bob5ob2o2bobo2b3ob3o3bob2obo2bo3bo3bo$obo2bob3o5b2o4b2o3b3o2b4o2b 3o3bobo2bob2ob5o3bobo$2bobo3b2ob2obob4o7b2o3bo2b3o2bob2o2b2obo2b3ob2o bo2bo$b2o6b3obo2bo2bo2bo2b6o2b2ob6o3b2o4bob5obobo$2bob3ob2o2b4o3bo2b4o bobo2bobo2b2obobob2o3bobo4bo3b2obo$6b3ob2o2bob2o2b2obo2bobo2bo2b2o4bo bo3b2o2bobob2o2b3ob2o$3b4obobo9b4ob2obobo3bobob2o3bob3obobo2bo3bob4o$ o2bob3obobo2b3o3bo2b3obo3b3obob7o3bob2o2b3o2bo2bobo$4b2o2bobobo3b4ob4o 3b3o4b4obobobobo2bo3b6o$2bob2o2b4o3b2ob2o2b3ob2o2bob4o4bo2bo4bob3ob3o 2bo2bo$4b2o3bo6b2o2bo4b2o2b4ob2o4b2o2bo3bobobo3b2obo3bo$3bo2b2ob4o3b3o bo6b2ob2o2bobob2o4bo4bobo4bo6bo$3ob2ob2ob2o2bo3bo3b3ob2ob2o3bo2b4o2bo b2ob4o2bobo2b3o$2o5b2obo3bo2bo4b2ob4o2bo2b5obob3ob5o3bo2b2obob2o$4bo2b obo3bobo2b2ob3o7b3o3bo3bo2b3o3b2o2b2ob2obobo$obo3b3o2b4o2b2obob7o3b4o b2o2b2o4b3ob2o5bobo2bo$2ob2obob2obo2bo3b2o2bo2bo2b3ob2ob5ob3ob2o4bob2o 3b3o2bo$o3bobob2obobobobob2ob2o4bob2obobo2b3o5bob4o3b2ob5o$bo3bo2b3ob 2o4bo2b2obo7bo3bob2o8bobo3bo2b4obo$6b8ob3o2b2obo3bo2bob3o3bob3o3b3o2b 2ob2ob6o$2bobo4bob2ob8o2bobob3o3bobo2b2obo4b4o4b8o$b3ob8o4bobo2b5ob3o 2b6obob2obo2bob2o7bo3bo$o3bob2obob5ob5o2bo2b2ob2o2bo2b4o2bo4b2o2bo2b3o 2b2o$bob3obob3ob3o2b3obo2bo2bo2b3ob7obo2bo5b3o3bob2obo$2ob3ob4o2b2ob3o bob2o3bob2o2bobob3o2bob4ob2obob3o3bo2bo$2b2o2bob2ob3ob2o2bo2bob3o5bob 5o2bob5o2bob3obobo3bo$o4bo2b2o2bobo2bobo2b4obob4o2bob2o2bobo2bo2bo3b2o 2bo3b3o$2obob2o4b3o3bo3b2o2bo2bob5o3bo2bo2b2o2bob2o2bo2b5o$bo2b2o2b2o b2o2b2obo4bo2bobo4b4ob2o3bobobo2b2o2bobo2bo2b2o$o3bo4bob2o2b2o5b2o2b2o bob2obob3obob3ob2o4b3ob2obo$b3obo2b4obo3b6o2bob2o8bob2o4bo2b3o4b3o4b2o $2obo5bo2b2obobobo2b4ob2obo2b2ob2o3bo2b2ob4o2b2obobobobo$3bo2b2ob3obo 4b2o2b4o2b2o3b2obo3b3o6b3ob4o2bob3o$obo4bo2bob2ob2o2b2o2b2ob2o2b6obob 3obo5b2o2b4o2b4o$bob2o2bo6bobo2bob3o3bo2bob2o4bob2ob2o7bobobob6o$ob3o b2ob2obobo2bobob2ob4ob2o4b2o3b2o4b2o2bob4ob7o$b2obob3o3bo2b4o2bobob3o bobo2b3o2bo2bo2bob3obo3bo2bobobo! #C [[ THUMBSIZE 2 THEME 6 GRID GRIDMAJOR 0 SUPPRESS THUMBLAUNCH ]] #C [[ WIDTH 700 HEIGHT 700 AUTOSTART PAUSE 1 GPS 30 T 30 LOOP 200 ]] [[ T 30 T 50 ]] [[ X -25 Y 20 ZOOM 10 ]] [[ T 60 GPS 10 ]] [[ T 60 T 120 ]] [[ X -60 ZOOM 15 ]] [[ T 140 T 160 ]] [[ X 0 Y 0 ZOOM 6.1 ]]

An example of "spewing" behavior, from a 64x64 soup (click above to open LifeViewer)

Oscillators

Day & Night is home to many different periods of oscillators. Here are the smallest known examples of each period up to 16:

x = 183, y = 12, rule = B3678/S34678 2o5bo28b2o9b2o55bo77bo$2o5b2o5b4o7bo8b4o9b2o10bobo20b2o5b2o11bob3o9bo 2bo9bobo7b2o9b3o28b2o$8bo6b2o7b3o7b6o6b5o7b6o6b5o6b3o5b3o10b5o9b3obo9b o8b2o10b2o28b2o$15b2o8bo10b4o7b4o7b6o7b3o7b2o7b2o6b2o2b4o10b5o8bo11bo 9bo3bo7b2ob2o4b2o$15b2o18bob2o9bo9bo2b2o23bo11b9o8b5o8b2ob2o9b2o11b2o 6b4o3b4o$14b4o19b2o22b3o21b3o11b4o2b2o7b5o12bo10b2o11b2o7b9o$60b3o9bo 11b5o10b2o12b5o12bo32b4o3b4o$70b2o13b3o25bob3o11bobo31b2o4b2ob2o$72bo 13bo27bo2bo$70bo10b2o7b2o$71b2o8b3o5b3o$70bo11b2o5b2o! #C [[ THUMBSIZE 2 THEME 6 GRID GRIDMAJOR 0 SUPPRESS THUMBLAUNCH ]] #C [[ WIDTH 1250 HEIGHT 240 ZOOM 6.5 AUTOSTART GPS 6 ]]

(click above to open LifeViewer)

Spaceships

Many periods of c/2 spaceships are known, but different reduced speeds are common as well. The S8 transition allows many of the spaceships in Day & Night to be stable.

Rocket

The rocket was the first spaceship found in Day & Night, and it appears spontaneously from many reactions which have symmetry around a line. This spaceship is probably the reason that this particular Life rule was chosen for Day & Night. It is unexpectedly large and has the amazingly large period of 40.

x = 0, y = 0, rule = B3678/S34678 7b2o$8bo$4bo3bo3b2o$3b2ob8o9b2o$2b11obo3b2ob6o13b2o$b13o2b11o7bo4b3o$ 26o10b5obo$b13o2b11o7bo4b3o$2b11obo3b2ob6o13b2o$3b2ob8o9b2o$4bo3bo3b2o $8bo$7b2o! #C [[ THUMBSIZE 2 THEME 6 GRID GRIDMAJOR 0 SUPPRESS THUMBLAUNCH ]]

Rocket (click above to open LifeViewer) RLE: here Plaintext: here Catagolue: here

The rocket is easily generated from tiny predecessors.

x = 412, y = 102, rule = B3678/S34678 b2o$ob2o$8o$ob2o$b2o! #C [[ THUMBSIZE 2 THEME 6 GRID GRIDMAJOR 0 SUPPRESS THUMBLAUNCH ]]

Rocket predecessor (click above to open LifeViewer)

Elementary

Unsimplified speeds are yet to be tabulated here.

Green means a spaceship has been proven to have minimal population via LLSSS.

Speed	Period	Direction	Smallest known	Minimum # of cells
c/2	2	orthogonal	29P2H1V0	29
	4	orthogonal	18P4H2V0	18
3c/7	7	orthogonal	316P7H3V0	316
2c/5	5	orthogonal	164P5H2V0	164
c/3	3	orthogonal	35P3H1V0	35
2c/7	7	orthogonal	160P7H2V0	160
c/4	4	orthogonal	32P4H1V0	32
c/5	5	orthogonal	40P5H1V0	40
c/6	6	orthogonal	63P6H1V0	63
c/7	7	orthogonal	104P7H1V0	104
c/8	8	orthogonal	190P8H1V0	190
c/9	9	orthogonal	212P9H1V0	212
(2,1)c/5	5	oblique	343P5H2V1	343
(2,1)c/6	6	oblique	288P6H2V1	288
c/3	3	diagonal	12P3H1V1(Butterfly)	12
c/4	4	diagonal	24P4H1V1	24
c/5	5	diagonal	46P5H1V1	46
c/6	6	diagonal	76P6H1V1	76
c/7	7	diagonal	48P7H1V1	48
c/8	8	diagonal	176P8H1V1	176

x = 437, y = 103, rule = B3678/S34678 433bo$2b2ob4o5b3o9b5o4b5o13b3o10b3o12b3o11b4o6b4o7bo4bobo4bo8bo2bo5bo2bo15bo16bo5bo14b2o14b3o2b3o44bo14b3o11b3o17b3o15b2o33bo23bo35b2o$b3o3bobo3bobobo8b3obo4bob3o11b3ob3o6b3ob3o8b2ob2o12b2o3b2o3b2o8b2o3b3o3b2o8b2ob2o3b2ob2o14bobo14bobo3bobo13b2o12bob2o4b2obo40b4o13b2obo9b3obo15b5o14b3o31b3o22b3o30b2ob2o$4ob5o3b5o7bob2obo4bob2obo9b3o2b4ob2ob4o2b3o8bobobo11bo2b2o2b2o2bo9b2o2b3o2b2o8b2o4bobo4b2o13b3o14b3o3b3o26b14o39b5o10b3o2b2o11b2o15b6o12bo2b2o33bo21b4o28b4o2bo$b5o6bob3obo7b3o8b3o11b2o2b3ob4ob3o2b2o8b2o2bo13b10o12b2o3b2o10b3o2b5o2b3o13bobo33b2ob2ob2o9bo4b2o4bo39bob5o8bobo4b2o10b2o17b5o12b5o28b2o27b2o26b5ob3o$o3bo2b2o6bo11b2ob6ob2o11bob3o2bob4obo2b3obo8b4ob2o11b8o14b2ob2o12bobob5obobo31b2o5b2o9b2o2b2o2b2o8b2ob2o2b2ob2o39bob3obo7b4o2b4o10bo19b3o46bob2o22bob4o23bo3bo2b3o$14bobo9bo2b2o4b2o2bo10b3o5b6o5b3o8b2o2b2ob2o10bob2obo15b5o55b2o7b2o9b8o11bobo2bobo40bo2b5o5bo2bobo4b2o31bobo44bobobo21bo3bob2o23bo3b3o2bo$27b12o11bo7bo4bo7bo12b4o12bo2bo34bo9bo31bob2o3b2obo10b6o13b2o2b2o41b2obo9bo2b6o3bo29bobo13bo27b3obob3o17b2obo6b2o21b2o3bobobo$26bob10obo8b2o2bo6b4o6bo2b2o10bo2bo11b2o2b2o17bo41b3o15bobobobo10bob6obo10b8o39bob3obo7b3o3bobo34bo12bobo7bo21b2ob2obo17bobob2o2bob3o19b3ob2ob2obo$29b8o14bobo5bo2bo5bobo10bo15b3o4b3o57b3o15b2o3b2o12b6o13bob2obo41bo17bo2b2o47b2o7b2o16bob3ob4o18b2o2b2obo27bo2b3obo$25b2o3b6o3b2o10b2o16b2o8b4o13b3obo2bob3o54bo2bo2bo15bobo15b4o15bo2bo42bob2o17b2o45b2o9b3o15b8obo19bobo2bo24bo4bo2bo$26b2o2b6o2b2o10bo2b3o10b3o2bo7bo15b5o4b5o52bob5obo32b4o62b2o10bo6bobo47bobo6bob2o14b9o21bo2bo24b4o3b2o$26b2obob4obob2o13b2obo8bob2o9b2obo14b4o4b4o53b9o12b2obob2o13b4o14bo4bo43b2o9b3o4bo2b2o46bo2b3o2bob2o13bob5obo23b2obo20b3ob6obo$30b6o13b8o8b8o21b16o48b4ob5ob4o9b7o11b2ob2ob2o12b2o2b2o43b2o10bob2o2bo49bobobo5bo17b4o27b3o20bob6ob3o$28bo2b4o2bo12bob4o10b4obo21bob14obo47b2obob5obob2o10b5o13bob2obo12bobo2bobo41bobo9b2ob3o3bo46bo3bobo22b6o47bo2b8o$29b8o13b2ob4o8b4ob2o23b14o50b2o4bo4b2o9b3o3b3o10bo6bo9b5o2b5o39bo14bo4b3o49bo22bob2obo50b3ob3o2bo$27b12o13bo2bo10bo2bo24b2o2b8o2b2o55bo13b3o7b3o11b2o14b3o2b3o41b3o16bo2bo73b2o2bo48b2o2bo$27b12o15bo12bo31b6o75b5ob5o11b4o13b8o41b2obo15bobo74bo51bobo3b4o$28b10o18bo8bo31bo2b4o2bo75b7o14b2o11b3o3b2o3b3o38b2obo14bob2o125b6obo$30b6o19b2o8b2o29bob8obo72b11o11bo2bo11bo2bo4bo2bo34bo2bo2b2o15bo2b4o120b6obo2bo$24bob2o2b6o2b2obo14bo8bo30b2ob2o2b2ob2o76b3o15b4o11b2obob2obob2o34bob3o18bo5b2o117b8o$25b2o2bob4obo2b2o57b2o4b2o77b5o15b2o12b3ob4ob3o34b5o20bob4o117bob5o$24b5o3b2o3b5o56bo6bo78b3o14b6o12bob4obo36b3o19b3o2bobo119b7o$24b6o2b2o2b6o159bob2obo12b8o35b3obo17b4o122b9o$24b5ob6ob5o156b2o2b4o2b2o8b10o37bo19b2o2b2o115b2ob7o$22bob3o3bob2obo3b3obo153bo2b8o2bo8b8o33bob3o19bo4bo116b2o4b3o$23bo2bo3bo4bo3bo2bo154b14o6b12o31bo27bo118bobo2b3o$28bo8bo160b12o7b2ob6ob2o31b2o25b2obo115bobo3b2o$26bob3ob2ob3obo157bob10obo48bobo22b6o117bo2bobo$23b3ob2ob2o2b2ob2ob3o155b12o49b3o21bo2b4o118b4o2bo$24bo16bo156bo3bo2bo3bo11b4o32b7o16b2ob2ob2obo120bob2o$23b3o14b3o177b6o30bob4o18bo3bo4b3o117b2o$24bo16bo159b6o14b4o32b3obo20bo6bob2o118bo$23b3o4b6o4b3o157b8o11b2o4b2o30b2o22b2o3bo4bo$25bo4b2o2b2o4bo159bo2b2o2bo11bobo2bobo27b3ob3o22b2ob4o2bo$30bo4bo164bo2b2o2bo11b2ob2ob2o27bobobo22bobo2bo2b2o$30bob2obo166bo2bo48b4o25b2obo2bobo$30bob2obo185bo2bo31bo26bo2bo4b3o$221bo2bo30bo25bo2bobo4bobo$222b2o29bo2bo24b5o3b2o$254bob2o25b2obobobob2o$255b2o27b2o2bobob2o$283b2o6bo$254b3obo24b4o2b5o$255bobo27bo3b5o$253b5o25bob3ob3o$254bo27bob2o6bo$253bob2o27b2o$253b3o25b2o3bo$252b4o26bobo4b3o$251b3o29b4o3b2o$251b4o27bob2o$254bo29b3o$254b2o31b3o$254bo28bob6o$251bobo30b2obob2o$252b4o29bob2o$251b2ob2o27b2o2b4o$251b2o2bo27bo5b2o$250b3ob2o29b3ob2o$249bob3o30bob3o$251b3o32b2ob2o$248b2obo34bob2o$250b3o37b2o$248b3o2bo37bo$249b3obo35bob2o$246bo44b2o$246b2o2bo38b4o$247b2o36b6obo$245b3o34b2ob3ob2obo$244bo37b2ob3obo$244bobo36bob3obo$246b3o33bob4o$244bobob2o35bo$244b4o34b2o2bo$244b3ob2o34bo2b2o$242b2ob2ob2o35b4o$242bob3obo35b2ob2o$244bo38bo2bo$244b2o40bo$285b2o$245b2o$244b3o$244b3o$244b3o$242bob2o$242b3obo$242b4o$241bo2b2o$241bobo$242b2o$242b2o$244bo$241bo$241b2o$240bo$240bobo$238b5o$237b3o$237bob2o$235b5o$237bo$237bo! #C [[ THUMBSIZE 2 THEME 6 GRID GRIDMAJOR 0 SUPPRESS THUMBLAUNCH ]] #C [[ ZOOM 2 WIDTH 900 ]]

A collection of these ships (click above to open LifeViewer)

In February 2020, AforAmpere found the first knightships in D&N, of speeds (2,1)c/5 and (2,1)c/6 respectively. On October 26, 2020, Adam P. Goucher found a second, larger (2,1)c/5 knightship using ikpx2, and quickly found multiple tagalongs (including a period-10 tagalong) and a wickstretcher based on it. The same day, Goucher found a smaller and thinner (2,1)c/6 spaceship.

On October 27, Goucher found a "growing knightship" - a pattern in which the front end moves at (2,1)c/5 while the back end moves at (2,1)c/6.

These knightships were collectively voted OCA Discovery of the Year for 2020 on the ConwayLife.com forums.

Infinite growth

Day & Night has a few behavioral features that are typically unfavorable for gun construction, such as uncommon spaceships and little to no recurring evolutionary sequences. Nevertheless, many guns have been constructed in the rule, mainly due to the existence of extensible sparky oscillators that can be constructed for a wide range of periods.

x = 505, y = 51, rule = B3678/S34678 99boo207boo97boo$80b4o336b6o$99boo8b4o195boo97boo22b4o12boo32boo$80b4o 8b4o8boo34b4o4b4o12b6o45boo10boo94boo14boo43boo26boo6b6o34b4o8boo$61b oo8boobb4o6boobboo8boo8b4o10boobb4obboo10boo6boobboobboo8boobb4o65boo 62boo24boo51boo6b4o8boo6b4o8boobb4o12boobb4o10boobboo4boo4boo8boobboo$ 57boobobb8obboo4b6obboobb8obb8o4b5oboobobboo4boobb10obb6obboobboobb8o bboo4boboo22boobboo4boo4boo4boo22b4o48b4o4b6obboobboobboobboo6boo4boo bb8o22boob5obb6o4b8obb6o4b8obboo4b5oboob3obboo4b10obboobb4obb4obb8obb oobb5oboo$57b23o4b8o4b8obb34o4b4o4b12o6b13o16boob3obboobb4obb4obb4obb 22o4b5oboo36boobo4b4o6boobboobboobboobb6obb4obboo8b3oboo16b5obb26obb6o 6b34o4b8obb31o$58b41obb8o4b69o17b45obb17o36b9obb24obb27o17b27obb22o4b 12obb32obb21o$58b22o4b8o4b8obb34o4b4o4b12o6b12o18b15obb10obb33o38b23o bb14obb21o18b4obb26obb6o6b34o4b8obb30o$60bobb8obboo4b6obboobb8obb8o4b 5oboobobboo4boobb10obb6obboobboobb8obboo4bo20b44obb16o38b8obb24obb26o 20b5obb6o4b8obb6o4b8obboo4b5oboob3obboo4b10obboobb4obb4obb8obboobb5o$ 61boo8boobb4o6boobboo8boo8b4o10boobb4obboo10boo6boobboobboo8boobb4o23b 3obboobb4obb4obb4obb22o4b5o42bo4b4o6boobboobboobboobb6obb4obboo8b3o27b oo6b4o8boo6b4o8boobb4o12boobb4o10boobboo4boo4boo8boobboo$80b4o8b4o8boo 34b4o4b4o12b6o35boobboo4boo4boo4boo22b4o48b4o4b6obboobboobboobboo6boo 4boobb8o27boo26boo6b6o34b4o8boo$99boo8b4o131boo62boo24boo71boo22b4o12b oo32boo$80b4o131boo10boo94boo14boo79b6o$99boo207boo97boo$$308boo3$7boo $5boobo$6b4oboo$3bob8o9boo68boobboo$bb10obo3boob3obo65b10o$b12obb11o 64b10o$24obbo62b10o$b12obb11o64b10o$bb10obo3boob3obo65b10o$3bob8o9boo 68boobboo$6b4oboo$5boobo$7boo3$308boo$$99boo207boo$80b4o131boo10boo94b oo14boo$99boo8b4o131boo62boo24boo111boo32boo$80b4o8b4o8boo99boobboo4b oo4boo4boo22b4o48b4o4b6obboobboobboobboo6boo4boobb8o103b4o8boo$61boo8b oobb4o6boobboo8boo8b4o89b3obboobb4obb4obb4obb22o4b5o42bo4b4o6boobboobb oobboobb6obb4obboo8b3o87boobb4o10boobboo4boo4boo8boobboo$60bobb8obboo 4b6obboobb8obb8o4b5o82b44obb16o38b8obb24obb26o82b3obboo4b10obboobb4obb 4obb8obboobb5o$58b22o4b8o4b8obb14o80b15obb10obb33o38b23obb14obb21o80b 18o4b8obb30o$58b41obb8o4b7o79b45obb17o36b9obb24obb27o79b5obb32obb21o$ 57b23o4b8o4b8obb15o78boob3obboobb4obb4obb4obb22o4b5oboo36boobo4b4o6boo bboobboobboobb6obb4obboo8b3oboo78b19o4b8obb31o$57boobobb8obboo4b6obboo bb8obb8o4b5oboo84boobboo4boo4boo4boo22b4o48b4o4b6obboobboobboobboo6boo 4boobb8o84boob3obboo4b10obboobb4obb4obb8obboobb5oboo$61boo8boobb4o6boo bboo8boo8b4o131boo62boo24boo111boobb4o10boobboo4boo4boo8boobboo$80b4o 8b4o8boo109boo10boo94boo14boo119b4o8boo$99boo8b4o195boo137boo32boo$80b 4o$99boo207boo! #C [[ THUMBSIZE 2 THEME 6 GRID GRIDMAJOR 0 SUPPRESS THUMBLAUNCH ]] #C [[ WIDTH 1500 HEIGHT 600 ZOOM 2.5 GPS 600 LOOP 3671 AUTOSTART ]]

A period-3671 rocket gun, one of many guns that utilize the extensible sparky oscillator. (click above to open LifeViewer)

External links

• David I. Bell (1997). "Day & Night - An Interesting Variant of Life". See also Bell's Day & Night pattern archive.
• Pete Carlton. "Pete's Game of Life Page: B3678 S34678".
• Day & Night (B3678/S34678) (discussion thread) at the ConwayLife.com forums
• Day & Night at Wikipedia
• Day & Night at Adam P. Goucher's Catagolue
• Day & Night at David Eppstein's Glider Database
• MCell built-in Life rules: Day & Night at Mirek Wójtowicz's Cellebration page
• The Rocket (glider 19979)