YES We show the termination of the TRS R: pred(s(x)) -> x minus(x,|0|()) -> x minus(x,s(y)) -> pred(minus(x,y)) quot(|0|(),s(y)) -> |0|() quot(s(x),s(y)) -> s(quot(minus(x,y),s(y))) log(s(|0|())) -> |0|() log(s(s(x))) -> s(log(s(quot(x,s(s(|0|())))))) -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: minus#(x,s(y)) -> pred#(minus(x,y)) p2: minus#(x,s(y)) -> minus#(x,y) p3: quot#(s(x),s(y)) -> quot#(minus(x,y),s(y)) p4: quot#(s(x),s(y)) -> minus#(x,y) p5: log#(s(s(x))) -> log#(s(quot(x,s(s(|0|()))))) p6: log#(s(s(x))) -> quot#(x,s(s(|0|()))) and R consists of: r1: pred(s(x)) -> x r2: minus(x,|0|()) -> x r3: minus(x,s(y)) -> pred(minus(x,y)) r4: quot(|0|(),s(y)) -> |0|() r5: quot(s(x),s(y)) -> s(quot(minus(x,y),s(y))) r6: log(s(|0|())) -> |0|() r7: log(s(s(x))) -> s(log(s(quot(x,s(s(|0|())))))) The estimated dependency graph contains the following SCCs: {p5} {p3} {p2} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: log#(s(s(x))) -> log#(s(quot(x,s(s(|0|()))))) and R consists of: r1: pred(s(x)) -> x r2: minus(x,|0|()) -> x r3: minus(x,s(y)) -> pred(minus(x,y)) r4: quot(|0|(),s(y)) -> |0|() r5: quot(s(x),s(y)) -> s(quot(minus(x,y),s(y))) r6: log(s(|0|())) -> |0|() r7: log(s(s(x))) -> s(log(s(quot(x,s(s(|0|())))))) The set of usable rules consists of r1, r2, r3, r4, r5, r6 Take the reduction pair: generalized weighted path order (>=MG, >G) base order 1: trivial reduction triple (T x T, T x T, Φ) base order 2: lexicographic combination of reduction triples: 1. marked-algebra reduction triple (>=A, >=A!, >A!): matrix interpretation with standard point-wise order: carrier: N^1 order: standard order interpretations: log#_A(x1) = x1 s_A(x1) = x1 + 2 quot_A(x1,x2) = x1 + 1 |0|_A() = 1 pred_A(x1) = x1 minus_A(x1,x2) = x1 log_A(x1) = x1 log#!_A(x1) = x1 s!_A(x1) = 2 quot!_A(x1,x2) = 2 |0|!_A() = 1 pred!_A(x1) = 0 minus!_A(x1,x2) = x1 + 1 log!_A(x1) = 3 2. marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: log#_A(x1) = max{0, x1 - 15} s_A(x1) = x1 + 7 quot_A(x1,x2) = x1 + 1 |0|_A = 0 pred_A(x1) = max{0, x1 - 1} minus_A(x1,x2) = x1 log_A(x1) = max{16, x1 + 8} log#!_A(x1) = x1 + 14 s!_A(x1) = x1 + 5 quot!_A(x1,x2) = x1 + 2 |0|!_A = 0 pred!_A(x1) = max{12, x1 + 7} minus!_A(x1,x2) = x2 + 4 log!_A(x1) = 0 partial status: pi(log#) = [] pi(s) = [1] pi(quot) = [] pi(|0|) = [] pi(pred) = [1] pi(minus) = [1, 2] pi(log) = [1] The following rules are removed: p1 Then no dependency pair remains. -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: quot#(s(x),s(y)) -> quot#(minus(x,y),s(y)) and R consists of: r1: pred(s(x)) -> x r2: minus(x,|0|()) -> x r3: minus(x,s(y)) -> pred(minus(x,y)) r4: quot(|0|(),s(y)) -> |0|() r5: quot(s(x),s(y)) -> s(quot(minus(x,y),s(y))) r6: log(s(|0|())) -> |0|() r7: log(s(s(x))) -> s(log(s(quot(x,s(s(|0|())))))) The set of usable rules consists of r1, r2, r3, r4, r6 Take the reduction pair: generalized weighted path order (>=MG, >G) base order 1: trivial reduction triple (T x T, T x T, Φ) base order 2: lexicographic combination of reduction triples: 1. marked-algebra reduction triple (>=A, >=A!, >A!): matrix interpretation with standard point-wise order: carrier: N^1 order: standard order interpretations: quot#_A(x1,x2) = x1 s_A(x1) = x1 + 2 minus_A(x1,x2) = x1 + 1 pred_A(x1) = x1 |0|_A() = 3 quot_A(x1,x2) = x1 + 1 log_A(x1) = x1 quot#!_A(x1,x2) = x2 s!_A(x1) = 3 minus!_A(x1,x2) = 1 pred!_A(x1) = 0 |0|!_A() = 0 quot!_A(x1,x2) = 2 log!_A(x1) = 1 2. marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: quot#_A(x1,x2) = max{0, x2 - 20} s_A(x1) = max{19, x1 + 7} minus_A(x1,x2) = max{13, x1 + 6, x2 - 20} pred_A(x1) = max{7, x1 - 7} |0|_A = 0 quot_A(x1,x2) = max{13, x1 - 21, x2 - 27} log_A(x1) = max{8, x1 - 28} quot#!_A(x1,x2) = max{15, x2 - 6} s!_A(x1) = 0 minus!_A(x1,x2) = max{14, x2 - 1} pred!_A(x1) = 17 |0|!_A = 16 quot!_A(x1,x2) = max{28, x1 - 22, x2 - 15} log!_A(x1) = x1 + 8 partial status: pi(quot#) = [1] pi(s) = [1] pi(minus) = [1] pi(pred) = [1] pi(|0|) = [] pi(quot) = [1] pi(log) = [] The following rules are removed: p1 Then no dependency pair remains. -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: minus#(x,s(y)) -> minus#(x,y) and R consists of: r1: pred(s(x)) -> x r2: minus(x,|0|()) -> x r3: minus(x,s(y)) -> pred(minus(x,y)) r4: quot(|0|(),s(y)) -> |0|() r5: quot(s(x),s(y)) -> s(quot(minus(x,y),s(y))) r6: log(s(|0|())) -> |0|() r7: log(s(s(x))) -> s(log(s(quot(x,s(s(|0|())))))) The set of usable rules consists of (no rules) Take the reduction pair: generalized weighted path order (>=MG, >G) base order 1: trivial reduction triple (T x T, T x T, Φ) base order 2: lexicographic combination of reduction triples: 1. marked-algebra reduction triple (>=A, >=A!, >A!): matrix interpretation with standard point-wise order: carrier: N^1 order: standard order interpretations: minus#_A(x1,x2) = x2 s_A(x1) = x1 + 3 minus#!_A(x1,x2) = x2 + 2 s!_A(x1) = x1 + 1 2. marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: minus#_A(x1,x2) = 0 s_A(x1) = max{5, x1 - 20} minus#!_A(x1,x2) = max{1, x1 - 1, x2 - 6} s!_A(x1) = x1 + 70 partial status: pi(minus#) = [1] pi(s) = [] The following rules are removed: p1 Then no dependency pair remains.