In the above pattern, there is a gun set up to produce loop-lengthening spaceships, but it is normally suppressed by a glider stream. One incoming glider is included to suppress the suppressing stream, thus releasing a spaceship to lengthen the loop. Initial bit contents of the loop are 01, based on a positive logic rightward stream. When the loop is lengthened, the new contents become 011 (a 1 is always what's inserted).

The output glider stream can be interpreted as as 010101011011011011... That is, the loop is lengthened after three full cycles.

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