Corner dot

A corner dot is a dot produced by a dot sparker, or occasionally naturally or via glider synthesis, located in the corner of a pattern. The dot is produced by three mutually adjacent cells (rather than a line of three cells) that all die in the same generation. Corner dots are similar to delayed dots in that the leading edge is in the same row or column for two consecutive generations, although the location of the on cells on the leading edge changes. An example list, nowhere near exhaustive, of notable corner dot sparkers is shown below.

Example list

3b2ob$2bo2bo$o2bobo$4bob$ob2o2b$bo! #C [[ THUMBSIZE 2 THEME 6 GRID GRIDMAJOR 0 SUPPRESS THUMBLAUNCH ]] #C [[ GPS 4 THUMBSIZE 2 ]] Mold (period 4) is a typical corner dot sparker, although it is more likely to fail than higher-period corner dot sparkers (click above to open LifeViewer) RLE: here Plaintext: here Catagolue: here	b2o5b$b2o5b2$bo6b$obo5b$o2bo2b2o$4bob2o$2b2o! #C [[ THUMBSIZE 2 THEME 6 GRID GRIDMAJOR 0 SUPPRESS THUMBLAUNCH ]] #C [[ GPS 4 THUMBSIZE 2 STARTFROM 4 ]] Unix (period 6) is also a typical corner dot sparker (click above to open LifeViewer) RLE: here Plaintext: here Catagolue: here
6bobob$5bo4b$2o2bo4bo$2obo2bob2o$4b2o! #C [[ THUMBSIZE 2 THEME 6 GRID GRIDMAJOR 0 SUPPRESS THUMBLAUNCH ]] #C [[ GPS 4 THUMBSIZE 2 ]] Blocker (period 8) is another typical corner dot sparker (click above to open LifeViewer) RLE: here Plaintext: here Catagolue: here	x = 20, y = 17, rule = B3/S23 5bo$3b5o$2bo5bo$2bo2b3o10b2o$b2obo13bo$o3b2o9b2obo$bobo2bo10bo$2ob2ob 2o5bo$7bo4bo$2ob2ob2o5bobo$bobo2bo$o3b2o$b2obo$2bo2b3o$2bo5bo$3b5o$5bo ! #C [[ THUMBSIZE 2 THEME 6 GRID GRIDMAJOR 0 SUPPRESS THUMBLAUNCH ]] #C [[ GPS 4 THUMBSIZE 2 ]] 66P13, using a rephased transparent blinker. The p47 pre-pulsar shuttle uses the same reaction (click above to open LifeViewer) RLE: here Plaintext: here Catagolue: here
x = 24, y = 17, rule = B3/S23 20b2o$11bo7bobo$9b3o8bo$8bo$8b2o$15bo$15bobo$16b3o3b2o$2o20b2o$2o3b3o$ 6bobo$8bo$14b2o$15bo$3bo8b3o$2bobo7bo$2b2o! #C [[ THUMBSIZE 2 THEME 6 GRID GRIDMAJOR 0 SUPPRESS THUMBLAUNCH ]] #C [[ GPS 18 THUMBSIZE 2 STARTFROM 11 ]] The p35 honey farm hassler produces corner dot sparks, which has been used to create LCMs, although the low clearance makes it difficult to produce hasslers utilising this spark (click above to open LifeViewer) RLE: here Plaintext: here Catagolue: here	x = 29, y = 29, rule = B3/S23 5b2o11b2o5b2o$4bo2bo10bo5bobo$4b2obo7bo3bo2b3o$5bob2o6b4o2bo3bo$o2bo3b o11b2ob2obo$4obob2o8bo2bo4bobo$8bo8b2o2b2o3bobo$2b3o3bo14b3o2bo$2bo2bo 2b2o13bo2b2o$3b2o4bob2ob2o3b2ob2obo$10bo4bo3bo3bobo$11bo11bobob2o$11bo 2bo2bo2bo4bobo$16bobo5bo2bo$15bo3bo5b2o$16bobo$11b2o4bo4b2o$11b2o9b2o 3$11bo11bo$10bobo9bobo$10bobo2b5o2bobo$7b2obo2bob5obo2bob2o$7b2obo4b5o 4bob2o$10bo13bo$10bobo4bo4bobo$11b2o4bo4b2o$17bo! #C [[ THUMBSIZE 2 THEME 6 GRID GRIDMAJOR 0 SUPPRESS THUMBLAUNCH ]] #C [[ GPS 10 THUMBSIZE 2 ZOOM 8 ]] An example of two p5 corner dot sparkers along with a p4 hassling a traffic light to form a period-20 oscillator (click above to open LifeViewer) Catagolue: here
x = 12, y = 12, rule = B3/S23 10b2o$7b2o2bo$6bobobo$6bo3b2o$4bob2o2bo$7b2obo$2b3o2bobo$bo2b3o$b2o2bo 2bo$6bo$ob4o$2obo! #C [[ THUMBSIZE 2 THEME 6 GRID GRIDMAJOR 0 SUPPRESS THUMBLAUNCH ]] #C [[ GPS 10 THUMBSIZE 2 ZOOM 16 ]] A p2 corner dot sparker, used for example in a p134 wing hassler. (click above to open LifeViewer) RLE: here Plaintext: here Catagolue: here

See also

• Clock, not a sparker, but can suppress births in the same way a corner dot can
• obo! spark, which often overlaps
• Sparking eater, which can create a corner dot with a glider.