YES After renaming modulo { a->0, b->1, c->2 }, it remains to prove termination of the 4-rule system { 0 -> , 0 -> 1 1 , 0 1 -> 0 2 0 2 , 2 2 -> } The system was reversed. After renaming modulo { 0->0, 1->1, 2->2 }, it remains to prove termination of the 4-rule system { 0 -> , 0 -> 1 1 , 1 0 -> 2 0 2 0 , 2 2 -> } Applying sparse 2-tiling [Hofbauer/Geser/Waldmann, FSCD 2019]. After renaming modulo { (0,0)->0, (0,1)->1, (0,2)->2, (0,4)->3, (1,0)->4, (1,1)->5, (1,2)->6, (1,4)->7, (2,0)->8, (2,1)->9, (2,2)->10, (2,4)->11, (3,0)->12, (3,1)->13, (3,2)->14, (3,4)->15 }, it remains to prove termination of the 64-rule system { 0 0 -> 0 , 0 1 -> 1 , 0 2 -> 2 , 0 3 -> 3 , 4 0 -> 4 , 4 1 -> 5 , 4 2 -> 6 , 4 3 -> 7 , 8 0 -> 8 , 8 1 -> 9 , 8 2 -> 10 , 8 3 -> 11 , 12 0 -> 12 , 12 1 -> 13 , 12 2 -> 14 , 12 3 -> 15 , 0 0 -> 1 5 4 , 0 1 -> 1 5 5 , 0 2 -> 1 5 6 , 0 3 -> 1 5 7 , 4 0 -> 5 5 4 , 4 1 -> 5 5 5 , 4 2 -> 5 5 6 , 4 3 -> 5 5 7 , 8 0 -> 9 5 4 , 8 1 -> 9 5 5 , 8 2 -> 9 5 6 , 8 3 -> 9 5 7 , 12 0 -> 13 5 4 , 12 1 -> 13 5 5 , 12 2 -> 13 5 6 , 12 3 -> 13 5 7 , 1 4 0 -> 2 8 2 8 0 , 1 4 1 -> 2 8 2 8 1 , 1 4 2 -> 2 8 2 8 2 , 1 4 3 -> 2 8 2 8 3 , 5 4 0 -> 6 8 2 8 0 , 5 4 1 -> 6 8 2 8 1 , 5 4 2 -> 6 8 2 8 2 , 5 4 3 -> 6 8 2 8 3 , 9 4 0 -> 10 8 2 8 0 , 9 4 1 -> 10 8 2 8 1 , 9 4 2 -> 10 8 2 8 2 , 9 4 3 -> 10 8 2 8 3 , 13 4 0 -> 14 8 2 8 0 , 13 4 1 -> 14 8 2 8 1 , 13 4 2 -> 14 8 2 8 2 , 13 4 3 -> 14 8 2 8 3 , 2 10 8 -> 0 , 2 10 9 -> 1 , 2 10 10 -> 2 , 2 10 11 -> 3 , 6 10 8 -> 4 , 6 10 9 -> 5 , 6 10 10 -> 6 , 6 10 11 -> 7 , 10 10 8 -> 8 , 10 10 9 -> 9 , 10 10 10 -> 10 , 10 10 11 -> 11 , 14 10 8 -> 12 , 14 10 9 -> 13 , 14 10 10 -> 14 , 14 10 11 -> 15 } The system was filtered by the following matrix interpretation of type E_J with J = {1,...,2} and dimension 2: 0 is interpreted by / \ | 1 4 | | 0 1 | \ / 1 is interpreted by / \ | 1 3 | | 0 1 | \ / 2 is interpreted by / \ | 1 2 | | 0 1 | \ / 3 is interpreted by / \ | 1 3 | | 0 1 | \ / 4 is interpreted by / \ | 1 2 | | 0 1 | \ / 5 is interpreted by / \ | 1 0 | | 0 1 | \ / 6 is interpreted by / \ | 1 0 | | 0 1 | \ / 7 is interpreted by / \ | 1 0 | | 0 1 | \ / 8 is interpreted by / \ | 1 0 | | 0 1 | \ / 9 is interpreted by / \ | 1 2 | | 0 1 | \ / 10 is interpreted by / \ | 1 2 | | 0 1 | \ / 11 is interpreted by / \ | 1 0 | | 0 1 | \ / 12 is interpreted by / \ | 1 0 | | 0 1 | \ / 13 is interpreted by / \ | 1 1 | | 0 1 | \ / 14 is interpreted by / \ | 1 0 | | 0 1 | \ / 15 is interpreted by / \ | 1 0 | | 0 1 | \ / After renaming modulo { 8->0, 2->1, 10->2, 0->3, 9->4, 5->5, 4->6, 6->7, 1->8, 3->9 }, it remains to prove termination of the 13-rule system { 0 1 -> 2 , 0 3 -> 4 5 6 , 0 1 -> 4 5 7 , 5 6 3 -> 7 0 1 0 3 , 5 6 8 -> 7 0 1 0 8 , 5 6 1 -> 7 0 1 0 1 , 5 6 9 -> 7 0 1 0 9 , 4 6 3 -> 2 0 1 0 3 , 4 6 8 -> 2 0 1 0 8 , 4 6 1 -> 2 0 1 0 1 , 4 6 9 -> 2 0 1 0 9 , 1 2 0 -> 3 , 7 2 0 -> 6 } Applying the dependency pairs transformation. After renaming modulo { (0,true)->0, (3,false)->1, (4,true)->2, (5,false)->3, (6,false)->4, (5,true)->5, (1,false)->6, (7,false)->7, (7,true)->8, (0,false)->9, (1,true)->10, (8,false)->11, (9,false)->12, (2,false)->13, (4,false)->14 }, it remains to prove termination of the 48-rule system { 0 1 -> 2 3 4 , 0 1 -> 5 4 , 0 6 -> 2 3 7 , 0 6 -> 5 7 , 0 6 -> 8 , 5 4 1 -> 8 9 6 9 1 , 5 4 1 -> 0 6 9 1 , 5 4 1 -> 10 9 1 , 5 4 1 -> 0 1 , 5 4 11 -> 8 9 6 9 11 , 5 4 11 -> 0 6 9 11 , 5 4 11 -> 10 9 11 , 5 4 11 -> 0 11 , 5 4 6 -> 8 9 6 9 6 , 5 4 6 -> 0 6 9 6 , 5 4 6 -> 10 9 6 , 5 4 6 -> 0 6 , 5 4 6 -> 10 , 5 4 12 -> 8 9 6 9 12 , 5 4 12 -> 0 6 9 12 , 5 4 12 -> 10 9 12 , 5 4 12 -> 0 12 , 2 4 1 -> 0 6 9 1 , 2 4 1 -> 10 9 1 , 2 4 1 -> 0 1 , 2 4 11 -> 0 6 9 11 , 2 4 11 -> 10 9 11 , 2 4 11 -> 0 11 , 2 4 6 -> 0 6 9 6 , 2 4 6 -> 10 9 6 , 2 4 6 -> 0 6 , 2 4 6 -> 10 , 2 4 12 -> 0 6 9 12 , 2 4 12 -> 10 9 12 , 2 4 12 -> 0 12 , 9 6 ->= 13 , 9 1 ->= 14 3 4 , 9 6 ->= 14 3 7 , 3 4 1 ->= 7 9 6 9 1 , 3 4 11 ->= 7 9 6 9 11 , 3 4 6 ->= 7 9 6 9 6 , 3 4 12 ->= 7 9 6 9 12 , 14 4 1 ->= 13 9 6 9 1 , 14 4 11 ->= 13 9 6 9 11 , 14 4 6 ->= 13 9 6 9 6 , 14 4 12 ->= 13 9 6 9 12 , 6 13 9 ->= 1 , 7 13 9 ->= 4 } The system was filtered by the following matrix interpretation of type E_J with J = {1,...,2} and dimension 2: 0 is interpreted by / \ | 1 0 | | 0 1 | \ / 1 is interpreted by / \ | 1 4 | | 0 1 | \ / 2 is interpreted by / \ | 1 1 | | 0 1 | \ / 3 is interpreted by / \ | 1 0 | | 0 1 | \ / 4 is interpreted by / \ | 1 2 | | 0 1 | \ / 5 is interpreted by / \ | 1 1 | | 0 1 | \ / 6 is interpreted by / \ | 1 2 | | 0 1 | \ / 7 is interpreted by / \ | 1 0 | | 0 1 | \ / 8 is interpreted by / \ | 1 0 | | 0 1 | \ / 9 is interpreted by / \ | 1 0 | | 0 1 | \ / 10 is interpreted by / \ | 1 0 | | 0 1 | \ / 11 is interpreted by / \ | 1 0 | | 0 1 | \ / 12 is interpreted by / \ | 1 0 | | 0 1 | \ / 13 is interpreted by / \ | 1 2 | | 0 1 | \ / 14 is interpreted by / \ | 1 2 | | 0 1 | \ / After renaming modulo { 9->0, 6->1, 13->2, 1->3, 14->4, 3->5, 4->6, 7->7, 11->8, 12->9 }, it remains to prove termination of the 13-rule system { 0 1 ->= 2 , 0 3 ->= 4 5 6 , 0 1 ->= 4 5 7 , 5 6 3 ->= 7 0 1 0 3 , 5 6 8 ->= 7 0 1 0 8 , 5 6 1 ->= 7 0 1 0 1 , 5 6 9 ->= 7 0 1 0 9 , 4 6 3 ->= 2 0 1 0 3 , 4 6 8 ->= 2 0 1 0 8 , 4 6 1 ->= 2 0 1 0 1 , 4 6 9 ->= 2 0 1 0 9 , 1 2 0 ->= 3 , 7 2 0 ->= 6 } The system is trivially terminating.