Blocker

	Blocker
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Pattern type	Oscillator
Number of cells	15
Bounding box	10 × 5
Period	8 (mod: 4)
Heat	9
Volatility	0.89 \| Unknown
Kinetic symmetry	Unspecified
Discovered by	Robert Wainwright
Year of discovery	Unknown
Rules
Outer-totalistic rules	B3/S23 – B378/S23678
# of rules	25 = 32
Glider synthesis
Fewest gliders	6
Uploaded synthesis RLE	blocker_synth.rle
Pattern files
Plaintext	blocker.cells
RLE	blocker.rle

Blocker is a period 8 oscillator found by Robert Wainwright. It is a useful dot sparker consisting of two blocks hassling an unnamed object. It reappears half way through its cycle rotated through 180 degrees.

Commonness

Blocker is about the sixteenth most common naturally-occurring oscillator in Achim Flammenkamp's census, being less common than mazing but more common than jam.^[1]