YES We show the termination of the TRS R: plus(x,|0|()) -> x plus(|0|(),y) -> y plus(s(x),y) -> s(plus(x,y)) times(|0|(),y) -> |0|() times(s(|0|()),y) -> y times(s(x),y) -> plus(y,times(x,y)) div(|0|(),y) -> |0|() div(x,y) -> quot(x,y,y) quot(|0|(),s(y),z) -> |0|() quot(s(x),s(y),z) -> quot(x,y,z) quot(x,|0|(),s(z)) -> s(div(x,s(z))) div(div(x,y),z) -> div(x,times(y,z)) eq(|0|(),|0|()) -> true() eq(s(x),|0|()) -> false() eq(|0|(),s(y)) -> false() eq(s(x),s(y)) -> eq(x,y) divides(y,x) -> eq(x,times(div(x,y),y)) prime(s(s(x))) -> pr(s(s(x)),s(x)) pr(x,s(|0|())) -> true() pr(x,s(s(y))) -> if(divides(s(s(y)),x),x,s(y)) if(true(),x,y) -> false() if(false(),x,y) -> pr(x,y) -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: plus#(s(x),y) -> plus#(x,y) p2: times#(s(x),y) -> plus#(y,times(x,y)) p3: times#(s(x),y) -> times#(x,y) p4: div#(x,y) -> quot#(x,y,y) p5: quot#(s(x),s(y),z) -> quot#(x,y,z) p6: quot#(x,|0|(),s(z)) -> div#(x,s(z)) p7: div#(div(x,y),z) -> div#(x,times(y,z)) p8: div#(div(x,y),z) -> times#(y,z) p9: eq#(s(x),s(y)) -> eq#(x,y) p10: divides#(y,x) -> eq#(x,times(div(x,y),y)) p11: divides#(y,x) -> times#(div(x,y),y) p12: divides#(y,x) -> div#(x,y) p13: prime#(s(s(x))) -> pr#(s(s(x)),s(x)) p14: pr#(x,s(s(y))) -> if#(divides(s(s(y)),x),x,s(y)) p15: pr#(x,s(s(y))) -> divides#(s(s(y)),x) p16: if#(false(),x,y) -> pr#(x,y) and R consists of: r1: plus(x,|0|()) -> x r2: plus(|0|(),y) -> y r3: plus(s(x),y) -> s(plus(x,y)) r4: times(|0|(),y) -> |0|() r5: times(s(|0|()),y) -> y r6: times(s(x),y) -> plus(y,times(x,y)) r7: div(|0|(),y) -> |0|() r8: div(x,y) -> quot(x,y,y) r9: quot(|0|(),s(y),z) -> |0|() r10: quot(s(x),s(y),z) -> quot(x,y,z) r11: quot(x,|0|(),s(z)) -> s(div(x,s(z))) r12: div(div(x,y),z) -> div(x,times(y,z)) r13: eq(|0|(),|0|()) -> true() r14: eq(s(x),|0|()) -> false() r15: eq(|0|(),s(y)) -> false() r16: eq(s(x),s(y)) -> eq(x,y) r17: divides(y,x) -> eq(x,times(div(x,y),y)) r18: prime(s(s(x))) -> pr(s(s(x)),s(x)) r19: pr(x,s(|0|())) -> true() r20: pr(x,s(s(y))) -> if(divides(s(s(y)),x),x,s(y)) r21: if(true(),x,y) -> false() r22: if(false(),x,y) -> pr(x,y) The estimated dependency graph contains the following SCCs: {p14, p16} {p4, p5, p6, p7} {p3} {p1} {p9} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: if#(false(),x,y) -> pr#(x,y) p2: pr#(x,s(s(y))) -> if#(divides(s(s(y)),x),x,s(y)) and R consists of: r1: plus(x,|0|()) -> x r2: plus(|0|(),y) -> y r3: plus(s(x),y) -> s(plus(x,y)) r4: times(|0|(),y) -> |0|() r5: times(s(|0|()),y) -> y r6: times(s(x),y) -> plus(y,times(x,y)) r7: div(|0|(),y) -> |0|() r8: div(x,y) -> quot(x,y,y) r9: quot(|0|(),s(y),z) -> |0|() r10: quot(s(x),s(y),z) -> quot(x,y,z) r11: quot(x,|0|(),s(z)) -> s(div(x,s(z))) r12: div(div(x,y),z) -> div(x,times(y,z)) r13: eq(|0|(),|0|()) -> true() r14: eq(s(x),|0|()) -> false() r15: eq(|0|(),s(y)) -> false() r16: eq(s(x),s(y)) -> eq(x,y) r17: divides(y,x) -> eq(x,times(div(x,y),y)) r18: prime(s(s(x))) -> pr(s(s(x)),s(x)) r19: pr(x,s(|0|())) -> true() r20: pr(x,s(s(y))) -> if(divides(s(s(y)),x),x,s(y)) r21: if(true(),x,y) -> false() r22: if(false(),x,y) -> pr(x,y) The set of usable rules consists of r13, r14, r15, r16, r17 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!): max/plus interpretation on natural numbers: if#_A(x1,x2,x3) = max{0, x1 - 60, x2 - 47, x3 - 24} false_A = 2 pr#_A(x1,x2) = max{0, x1 - 47, x2 - 45} s_A(x1) = x1 + 21 divides_A(x1,x2) = max{59, x1 - 5} eq_A(x1,x2) = 2 |0|_A = 22 true_A = 2 times_A(x1,x2) = max{0, x1 - 57} div_A(x1,x2) = max{16, x1 - 78, x2 - 41} if#!_A(x1,x2,x3) = max{9, x1 - 28, x3 - 10} false!_A = 11 pr#!_A(x1,x2) = max{1, x2 - 11} s!_A(x1) = max{27, x1 + 10} divides!_A(x1,x2) = max{32, x1 - 8, x2 - 16} eq!_A(x1,x2) = max{32, x1 - 23} |0|!_A = 33 true!_A = 28 times!_A(x1,x2) = max{32, x1 - 23, x2 - 8} div!_A(x1,x2) = max{x1 + 77, x2 + 94} 2. marked-algebra reduction triple (>=A, >=A!, >A!): matrix interpretation with standard point-wise order: carrier: N^1 order: standard order interpretations: if#_A(x1,x2,x3) = x3 false_A() = 1 pr#_A(x1,x2) = x2 s_A(x1) = x1 + 7 divides_A(x1,x2) = x2 + 2 eq_A(x1,x2) = 2 |0|_A() = 3 true_A() = 2 times_A(x1,x2) = x2 + 2 div_A(x1,x2) = x1 + x2 + 1 if#!_A(x1,x2,x3) = x3 + 8 false!_A() = 1 pr#!_A(x1,x2) = x2 + 7 s!_A(x1) = x1 + 9 divides!_A(x1,x2) = x1 + x2 + 6 eq!_A(x1,x2) = x1 + 6 |0|!_A() = 8 true!_A() = 0 times!_A(x1,x2) = x1 + 4 div!_A(x1,x2) = x1 + 14 partial status: pi(if#) = [] pi(false) = [] pi(pr#) = [] pi(s) = [1] pi(divides) = [2] pi(eq) = [1] pi(|0|) = [] pi(true) = [] pi(times) = [] pi(div) = [] The following rules are removed: p1, p2 Then no dependency pair remains. -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: div#(div(x,y),z) -> div#(x,times(y,z)) p2: div#(x,y) -> quot#(x,y,y) p3: quot#(x,|0|(),s(z)) -> div#(x,s(z)) p4: quot#(s(x),s(y),z) -> quot#(x,y,z) and R consists of: r1: plus(x,|0|()) -> x r2: plus(|0|(),y) -> y r3: plus(s(x),y) -> s(plus(x,y)) r4: times(|0|(),y) -> |0|() r5: times(s(|0|()),y) -> y r6: times(s(x),y) -> plus(y,times(x,y)) r7: div(|0|(),y) -> |0|() r8: div(x,y) -> quot(x,y,y) r9: quot(|0|(),s(y),z) -> |0|() r10: quot(s(x),s(y),z) -> quot(x,y,z) r11: quot(x,|0|(),s(z)) -> s(div(x,s(z))) r12: div(div(x,y),z) -> div(x,times(y,z)) r13: eq(|0|(),|0|()) -> true() r14: eq(s(x),|0|()) -> false() r15: eq(|0|(),s(y)) -> false() r16: eq(s(x),s(y)) -> eq(x,y) r17: divides(y,x) -> eq(x,times(div(x,y),y)) r18: prime(s(s(x))) -> pr(s(s(x)),s(x)) r19: pr(x,s(|0|())) -> true() r20: pr(x,s(s(y))) -> if(divides(s(s(y)),x),x,s(y)) r21: if(true(),x,y) -> false() r22: if(false(),x,y) -> pr(x,y) The set of usable rules consists of r1, r2, r5, r7 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!): max/plus interpretation on natural numbers: div#_A(x1,x2) = max{1, x1 - 25} div_A(x1,x2) = max{24, x1 + 21, x2 - 119} times_A(x1,x2) = max{x1 - 145, x2 + 29} quot#_A(x1,x2,x3) = max{1, x1 - 25} |0|_A = 1 s_A(x1) = x1 + 63 plus_A(x1,x2) = max{54, x1 + 53, x2 + 19} div#!_A(x1,x2) = x1 + 7 div!_A(x1,x2) = max{8, x1 - 22, x2 - 145} times!_A(x1,x2) = max{32, x1 - 62, x2 - 7} quot#!_A(x1,x2,x3) = x1 + 7 |0|!_A = 3 s!_A(x1) = max{5, x1 - 20} plus!_A(x1,x2) = max{33, x2 - 30} 2. marked-algebra reduction triple (>=A, >=A!, >A!): matrix interpretation with standard point-wise order: carrier: N^1 order: standard order interpretations: div#_A(x1,x2) = x1 div_A(x1,x2) = x1 + 7 times_A(x1,x2) = x1 + x2 + 8 quot#_A(x1,x2,x3) = x1 |0|_A() = 9 s_A(x1) = x1 + 3 plus_A(x1,x2) = x1 + x2 + 4 div#!_A(x1,x2) = 2 div!_A(x1,x2) = x1 + x2 + 1 times!_A(x1,x2) = x1 quot#!_A(x1,x2,x3) = 2 |0|!_A() = 3 s!_A(x1) = x1 + 5 plus!_A(x1,x2) = x2 + 6 partial status: pi(div#) = [] pi(div) = [] pi(times) = [1, 2] pi(quot#) = [] pi(|0|) = [] pi(s) = [1] pi(plus) = [1, 2] The following rules are removed: p1, p4 -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: div#(x,y) -> quot#(x,y,y) p2: quot#(x,|0|(),s(z)) -> div#(x,s(z)) and R consists of: r1: plus(x,|0|()) -> x r2: plus(|0|(),y) -> y r3: plus(s(x),y) -> s(plus(x,y)) r4: times(|0|(),y) -> |0|() r5: times(s(|0|()),y) -> y r6: times(s(x),y) -> plus(y,times(x,y)) r7: div(|0|(),y) -> |0|() r8: div(x,y) -> quot(x,y,y) r9: quot(|0|(),s(y),z) -> |0|() r10: quot(s(x),s(y),z) -> quot(x,y,z) r11: quot(x,|0|(),s(z)) -> s(div(x,s(z))) r12: div(div(x,y),z) -> div(x,times(y,z)) r13: eq(|0|(),|0|()) -> true() r14: eq(s(x),|0|()) -> false() r15: eq(|0|(),s(y)) -> false() r16: eq(s(x),s(y)) -> eq(x,y) r17: divides(y,x) -> eq(x,times(div(x,y),y)) r18: prime(s(s(x))) -> pr(s(s(x)),s(x)) r19: pr(x,s(|0|())) -> true() r20: pr(x,s(s(y))) -> if(divides(s(s(y)),x),x,s(y)) r21: if(true(),x,y) -> false() r22: if(false(),x,y) -> pr(x,y) The estimated dependency graph contains the following SCCs: {p1, p2} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: div#(x,y) -> quot#(x,y,y) p2: quot#(x,|0|(),s(z)) -> div#(x,s(z)) and R consists of: r1: plus(x,|0|()) -> x r2: plus(|0|(),y) -> y r3: plus(s(x),y) -> s(plus(x,y)) r4: times(|0|(),y) -> |0|() r5: times(s(|0|()),y) -> y r6: times(s(x),y) -> plus(y,times(x,y)) r7: div(|0|(),y) -> |0|() r8: div(x,y) -> quot(x,y,y) r9: quot(|0|(),s(y),z) -> |0|() r10: quot(s(x),s(y),z) -> quot(x,y,z) r11: quot(x,|0|(),s(z)) -> s(div(x,s(z))) r12: div(div(x,y),z) -> div(x,times(y,z)) r13: eq(|0|(),|0|()) -> true() r14: eq(s(x),|0|()) -> false() r15: eq(|0|(),s(y)) -> false() r16: eq(s(x),s(y)) -> eq(x,y) r17: divides(y,x) -> eq(x,times(div(x,y),y)) r18: prime(s(s(x))) -> pr(s(s(x)),s(x)) r19: pr(x,s(|0|())) -> true() r20: pr(x,s(s(y))) -> if(divides(s(s(y)),x),x,s(y)) r21: if(true(),x,y) -> false() r22: if(false(),x,y) -> pr(x,y) The set of usable rules consists of r7 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!): max/plus interpretation on natural numbers: div#_A(x1,x2) = max{0, x1 - 2, x2 - 15} quot#_A(x1,x2,x3) = max{0, x1 - 2, x2 - 15, x3 - 15} |0|_A = 7 s_A(x1) = max{14, x1 + 4} div_A(x1,x2) = max{7, x1 - 7} div#!_A(x1,x2) = max{2, x1 + 1, x2 - 15} quot#!_A(x1,x2,x3) = max{2, x1 + 1, x2 - 15, x3 - 15} |0|!_A = 0 s!_A(x1) = 0 div!_A(x1,x2) = 0 2. marked-algebra reduction triple (>=A, >=A!, >A!): matrix interpretation with standard point-wise order: carrier: N^1 order: standard order interpretations: div#_A(x1,x2) = x2 quot#_A(x1,x2,x3) = x3 |0|_A() = 6 s_A(x1) = 4 div_A(x1,x2) = x1 + x2 + 2 div#!_A(x1,x2) = x2 + 3 quot#!_A(x1,x2,x3) = x2 + 2 |0|!_A() = 6 s!_A(x1) = 9 div!_A(x1,x2) = x1 + x2 + 4 partial status: pi(div#) = [] pi(quot#) = [] pi(|0|) = [] pi(s) = [] pi(div) = [1] The following rules are removed: p1, p2 Then no dependency pair remains. -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: times#(s(x),y) -> times#(x,y) and R consists of: r1: plus(x,|0|()) -> x r2: plus(|0|(),y) -> y r3: plus(s(x),y) -> s(plus(x,y)) r4: times(|0|(),y) -> |0|() r5: times(s(|0|()),y) -> y r6: times(s(x),y) -> plus(y,times(x,y)) r7: div(|0|(),y) -> |0|() r8: div(x,y) -> quot(x,y,y) r9: quot(|0|(),s(y),z) -> |0|() r10: quot(s(x),s(y),z) -> quot(x,y,z) r11: quot(x,|0|(),s(z)) -> s(div(x,s(z))) r12: div(div(x,y),z) -> div(x,times(y,z)) r13: eq(|0|(),|0|()) -> true() r14: eq(s(x),|0|()) -> false() r15: eq(|0|(),s(y)) -> false() r16: eq(s(x),s(y)) -> eq(x,y) r17: divides(y,x) -> eq(x,times(div(x,y),y)) r18: prime(s(s(x))) -> pr(s(s(x)),s(x)) r19: pr(x,s(|0|())) -> true() r20: pr(x,s(s(y))) -> if(divides(s(s(y)),x),x,s(y)) r21: if(true(),x,y) -> false() r22: if(false(),x,y) -> pr(x,y) 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!): max/plus interpretation on natural numbers: times#_A(x1,x2) = x1 s_A(x1) = x1 + 13 times#!_A(x1,x2) = max{2, x1 - 1} s!_A(x1) = x1 + 28 2. marked-algebra reduction triple (>=A, >=A!, >A!): matrix interpretation with standard point-wise order: carrier: N^1 order: standard order interpretations: times#_A(x1,x2) = x1 s_A(x1) = x1 + 1 times#!_A(x1,x2) = x1 s!_A(x1) = 4 partial status: pi(times#) = [] pi(s) = [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: plus#(s(x),y) -> plus#(x,y) and R consists of: r1: plus(x,|0|()) -> x r2: plus(|0|(),y) -> y r3: plus(s(x),y) -> s(plus(x,y)) r4: times(|0|(),y) -> |0|() r5: times(s(|0|()),y) -> y r6: times(s(x),y) -> plus(y,times(x,y)) r7: div(|0|(),y) -> |0|() r8: div(x,y) -> quot(x,y,y) r9: quot(|0|(),s(y),z) -> |0|() r10: quot(s(x),s(y),z) -> quot(x,y,z) r11: quot(x,|0|(),s(z)) -> s(div(x,s(z))) r12: div(div(x,y),z) -> div(x,times(y,z)) r13: eq(|0|(),|0|()) -> true() r14: eq(s(x),|0|()) -> false() r15: eq(|0|(),s(y)) -> false() r16: eq(s(x),s(y)) -> eq(x,y) r17: divides(y,x) -> eq(x,times(div(x,y),y)) r18: prime(s(s(x))) -> pr(s(s(x)),s(x)) r19: pr(x,s(|0|())) -> true() r20: pr(x,s(s(y))) -> if(divides(s(s(y)),x),x,s(y)) r21: if(true(),x,y) -> false() r22: if(false(),x,y) -> pr(x,y) 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!): max/plus interpretation on natural numbers: plus#_A(x1,x2) = x1 s_A(x1) = max{14, x1} plus#!_A(x1,x2) = max{25, x1 + 24} s!_A(x1) = x1 + 25 2. marked-algebra reduction triple (>=A, >=A!, >A!): matrix interpretation with standard point-wise order: carrier: N^1 order: standard order interpretations: plus#_A(x1,x2) = x1 s_A(x1) = x1 + 2 plus#!_A(x1,x2) = x1 + 7 s!_A(x1) = x1 + 7 partial status: pi(plus#) = [] pi(s) = [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: eq#(s(x),s(y)) -> eq#(x,y) and R consists of: r1: plus(x,|0|()) -> x r2: plus(|0|(),y) -> y r3: plus(s(x),y) -> s(plus(x,y)) r4: times(|0|(),y) -> |0|() r5: times(s(|0|()),y) -> y r6: times(s(x),y) -> plus(y,times(x,y)) r7: div(|0|(),y) -> |0|() r8: div(x,y) -> quot(x,y,y) r9: quot(|0|(),s(y),z) -> |0|() r10: quot(s(x),s(y),z) -> quot(x,y,z) r11: quot(x,|0|(),s(z)) -> s(div(x,s(z))) r12: div(div(x,y),z) -> div(x,times(y,z)) r13: eq(|0|(),|0|()) -> true() r14: eq(s(x),|0|()) -> false() r15: eq(|0|(),s(y)) -> false() r16: eq(s(x),s(y)) -> eq(x,y) r17: divides(y,x) -> eq(x,times(div(x,y),y)) r18: prime(s(s(x))) -> pr(s(s(x)),s(x)) r19: pr(x,s(|0|())) -> true() r20: pr(x,s(s(y))) -> if(divides(s(s(y)),x),x,s(y)) r21: if(true(),x,y) -> false() r22: if(false(),x,y) -> pr(x,y) 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!): max/plus interpretation on natural numbers: eq#_A(x1,x2) = max{x1, x2} s_A(x1) = x1 + 24 eq#!_A(x1,x2) = max{4, x1 - 19, x2 - 13} s!_A(x1) = max{3, x1 - 14} 2. marked-algebra reduction triple (>=A, >=A!, >A!): matrix interpretation with standard point-wise order: carrier: N^1 order: standard order interpretations: eq#_A(x1,x2) = x1 + x2 s_A(x1) = x1 + 2 eq#!_A(x1,x2) = x2 + 6 s!_A(x1) = 5 partial status: pi(eq#) = [] pi(s) = [] The following rules are removed: p1 Then no dependency pair remains.