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          jolsonp9https://conwaylife.com/wiki/Jolson https://www.conwaylife.com/patterns/jolsonp9.rle Size:22x24 | Rule:23/3 
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          jamon34p13.1The smallest known period 39 oscillator as of April 2009, though it is usually considered trivial because there is no individual cell that oscillates at the full period. Size:21x16 | Rule:23/3 | @lifewiki 
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          jasonsp6https://conwaylife.com/wiki/Jason%27s_p6 https://conwaylife.com/patterns/jasonsp6.rle Size:10x10 | Rule:23/3 
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          jasonsp33https://conwaylife.com/wiki/Jason%27s_p33 https://www.conwaylife.com/patterns/jasonsp33.rle Size:30x24 | Rule:23/3 
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          jaggedlinesJagged lines of gliders, formed by a drifting collision of two LWSS streams, crash to form an approximately vertical jagged line of pairs of blocks. I don't know if the line stays within a bounded distance of the center line, or extends infinitely far to the left, or to the right, or both. https://www.conwaylife.com/wiki/Jagged_lines Size:125x67 | Rule:23/3 
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          jawsA 150-cell breeder found by Nick Gotts in 1997. https://conwaylife.com/wiki/Jaws Size:654x2881 | Rule:23/3 
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          jasonsp22on30p25https://conwaylife.com/wiki/30P25 https://www.conwaylife.com/patterns/jasonsp22on30p25.rle Size:20x42 | Rule:23/3 
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          jormungantsgtohhttps://conwaylife.com/wiki/Jormungant%27s_G-to-H https://conwaylife.com/patterns/jormungantsgtoh.rle Size:27x57 | Rule:23/3 
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          jack_synthGlider synthesis of jack. https://www.conwaylife.com/ref/mniemiec/objname.htm#J Size:114x106 | Rule:23/3 
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          justyna_synthGlider synthesis of Justyna. https://conwaylife.com/wiki/Justyna Size:55x41 | Rule:23/3 
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          jasonsp156Oscillator, or actually an eight-barrelled glider gun, discovered in a RandomAgar search. Also known as "92p156". https://conwaylife.com/wiki/Jason%27s_p156 https://conwaylife.com/patterns/jasonsp156.rle Size:42x42 | Rule:23/3 
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          jasonsp33.1https://conwaylife.com/wiki/Jason%27s_p33 https://www.conwaylife.com/patterns/jasonsp33.1.rle Size:34x30 | Rule:23/3 
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          jasonsp11A period 11 oscillator. https://www.conwaylife.com/wiki/Jason%27s_p11 Size:25x25 | Rule:23/3 
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          jolson_synthGlider syntheses of Jolson. https://www.conwaylife.com/ref/mniemiec/objname.htm#a Size:100x100 | Rule:23/3 
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          jsp36https://conwaylife.com/wiki/Jason%27s_p36 https://conwaylife.com/patterns/jsp36.rle Size:39x18 | Rule:23/3 
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          jamon44p7.2The smallest known non-trivial period 21 oscillator. Has a single cell that oscillates at the full period. Size:17x16 | Rule:23/3 | @lifewiki 
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          jasonsp36caterers_synth28-glider synthesis of Jason's p36 with caterers https://conwaylife.com/wiki/Jason%27s_p36 https://conwaylife.com/forums/viewtopic.php?f=2&p=58086#p58086 Size:228x45 | Rule:23/3 
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          jaydothttps://conwaylife.com/wiki/Jaydot https://conwaylife.com/patterns/jaydot.rle Size:3x6 | Rule:23/3 
 
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
              