Certification Problem
Input (TPDB SRS_Standard/Zantema_04/z082)
The rewrite relation of the following TRS is considered.
a(c(a(x1))) |
→ |
c(a(c(x1))) |
(1) |
a(a(b(x1))) |
→ |
a(d(b(x1))) |
(2) |
a(b(x1)) |
→ |
b(a(a(x1))) |
(3) |
d(d(x1)) |
→ |
a(d(b(x1))) |
(4) |
b(b(x1)) |
→ |
b(c(x1)) |
(5) |
a(d(c(x1))) |
→ |
c(a(x1)) |
(6) |
b(c(x1)) |
→ |
a(a(a(x1))) |
(7) |
Property / Task
Prove or disprove termination.Answer / Result
Yes.Proof (by matchbox @ termCOMP 2023)
1 Closure Under Flat Contexts
Using the flat contexts
{d(☐), c(☐), b(☐), a(☐)}
We obtain the transformed TRS
d(a(c(a(x1)))) |
→ |
d(c(a(c(x1)))) |
(8) |
d(a(a(b(x1)))) |
→ |
d(a(d(b(x1)))) |
(9) |
d(a(b(x1))) |
→ |
d(b(a(a(x1)))) |
(10) |
d(d(d(x1))) |
→ |
d(a(d(b(x1)))) |
(11) |
d(b(b(x1))) |
→ |
d(b(c(x1))) |
(12) |
d(a(d(c(x1)))) |
→ |
d(c(a(x1))) |
(13) |
d(b(c(x1))) |
→ |
d(a(a(a(x1)))) |
(14) |
c(a(c(a(x1)))) |
→ |
c(c(a(c(x1)))) |
(15) |
c(a(a(b(x1)))) |
→ |
c(a(d(b(x1)))) |
(16) |
c(a(b(x1))) |
→ |
c(b(a(a(x1)))) |
(17) |
c(d(d(x1))) |
→ |
c(a(d(b(x1)))) |
(18) |
c(b(b(x1))) |
→ |
c(b(c(x1))) |
(19) |
c(a(d(c(x1)))) |
→ |
c(c(a(x1))) |
(20) |
c(b(c(x1))) |
→ |
c(a(a(a(x1)))) |
(21) |
b(a(c(a(x1)))) |
→ |
b(c(a(c(x1)))) |
(22) |
b(a(a(b(x1)))) |
→ |
b(a(d(b(x1)))) |
(23) |
b(a(b(x1))) |
→ |
b(b(a(a(x1)))) |
(24) |
b(d(d(x1))) |
→ |
b(a(d(b(x1)))) |
(25) |
b(b(b(x1))) |
→ |
b(b(c(x1))) |
(26) |
b(a(d(c(x1)))) |
→ |
b(c(a(x1))) |
(27) |
b(b(c(x1))) |
→ |
b(a(a(a(x1)))) |
(28) |
a(a(c(a(x1)))) |
→ |
a(c(a(c(x1)))) |
(29) |
a(a(a(b(x1)))) |
→ |
a(a(d(b(x1)))) |
(30) |
a(a(b(x1))) |
→ |
a(b(a(a(x1)))) |
(31) |
a(d(d(x1))) |
→ |
a(a(d(b(x1)))) |
(32) |
a(b(b(x1))) |
→ |
a(b(c(x1))) |
(33) |
a(a(d(c(x1)))) |
→ |
a(c(a(x1))) |
(34) |
a(b(c(x1))) |
→ |
a(a(a(a(x1)))) |
(35) |
1.1 Semantic Labeling
The following interpretations form a
model
of the rules.
As carrier we take the set
{0,...,3}.
Symbols are labeled by the interpretation of their arguments using the interpretations
(modulo 4):
[d(x1)] |
= |
4x1 + 0 |
[c(x1)] |
= |
4x1 + 1 |
[b(x1)] |
= |
4x1 + 2 |
[a(x1)] |
= |
4x1 + 3 |
We obtain the labeled TRS
There are 112 ruless (increase limit for explicit display).
1.1.1 Rule Removal
Using the
matrix interpretations of dimension 1 with strict dimension 1 over the rationals with delta = 1
[d0(x1)] |
= |
x1 +
|
[d1(x1)] |
= |
x1 +
|
[d2(x1)] |
= |
x1 +
|
[d3(x1)] |
= |
x1 +
|
[c0(x1)] |
= |
x1 +
|
[c1(x1)] |
= |
x1 +
|
[c2(x1)] |
= |
x1 +
|
[c3(x1)] |
= |
x1 +
|
[b0(x1)] |
= |
x1 +
|
[b1(x1)] |
= |
x1 +
|
[b2(x1)] |
= |
x1 +
|
[b3(x1)] |
= |
x1 +
|
[a0(x1)] |
= |
x1 +
|
[a1(x1)] |
= |
x1 +
|
[a2(x1)] |
= |
x1 +
|
[a3(x1)] |
= |
x1 +
|
all of the following rules can be deleted.
a3(a1(c3(a2(x1)))) |
→ |
a1(c3(a1(c2(x1)))) |
(38) |
a3(a1(c3(a0(x1)))) |
→ |
a1(c3(a1(c0(x1)))) |
(39) |
c3(a1(c3(a2(x1)))) |
→ |
c1(c3(a1(c2(x1)))) |
(42) |
c3(a1(c3(a0(x1)))) |
→ |
c1(c3(a1(c0(x1)))) |
(43) |
b3(a1(c3(a2(x1)))) |
→ |
b1(c3(a1(c2(x1)))) |
(46) |
b3(a1(c3(a0(x1)))) |
→ |
b1(c3(a1(c0(x1)))) |
(47) |
d3(a1(c3(a3(x1)))) |
→ |
d1(c3(a1(c3(x1)))) |
(48) |
d3(a1(c3(a1(x1)))) |
→ |
d1(c3(a1(c1(x1)))) |
(49) |
d3(a1(c3(a2(x1)))) |
→ |
d1(c3(a1(c2(x1)))) |
(50) |
d3(a1(c3(a0(x1)))) |
→ |
d1(c3(a1(c0(x1)))) |
(51) |
a3(a3(a2(b3(x1)))) |
→ |
a3(a0(d2(b3(x1)))) |
(52) |
a3(a3(a2(b1(x1)))) |
→ |
a3(a0(d2(b1(x1)))) |
(53) |
a3(a3(a2(b2(x1)))) |
→ |
a3(a0(d2(b2(x1)))) |
(54) |
a3(a3(a2(b0(x1)))) |
→ |
a3(a0(d2(b0(x1)))) |
(55) |
c3(a3(a2(b3(x1)))) |
→ |
c3(a0(d2(b3(x1)))) |
(56) |
c3(a3(a2(b1(x1)))) |
→ |
c3(a0(d2(b1(x1)))) |
(57) |
c3(a3(a2(b2(x1)))) |
→ |
c3(a0(d2(b2(x1)))) |
(58) |
c3(a3(a2(b0(x1)))) |
→ |
c3(a0(d2(b0(x1)))) |
(59) |
b3(a3(a2(b3(x1)))) |
→ |
b3(a0(d2(b3(x1)))) |
(60) |
b3(a3(a2(b1(x1)))) |
→ |
b3(a0(d2(b1(x1)))) |
(61) |
b3(a3(a2(b2(x1)))) |
→ |
b3(a0(d2(b2(x1)))) |
(62) |
b3(a3(a2(b0(x1)))) |
→ |
b3(a0(d2(b0(x1)))) |
(63) |
d3(a3(a2(b3(x1)))) |
→ |
d3(a0(d2(b3(x1)))) |
(64) |
d3(a3(a2(b1(x1)))) |
→ |
d3(a0(d2(b1(x1)))) |
(65) |
d3(a3(a2(b2(x1)))) |
→ |
d3(a0(d2(b2(x1)))) |
(66) |
d3(a3(a2(b0(x1)))) |
→ |
d3(a0(d2(b0(x1)))) |
(67) |
a3(a2(b0(x1))) |
→ |
a2(b3(a3(a0(x1)))) |
(71) |
c3(a2(b3(x1))) |
→ |
c2(b3(a3(a3(x1)))) |
(72) |
c3(a2(b1(x1))) |
→ |
c2(b3(a3(a1(x1)))) |
(73) |
c3(a2(b2(x1))) |
→ |
c2(b3(a3(a2(x1)))) |
(74) |
c3(a2(b0(x1))) |
→ |
c2(b3(a3(a0(x1)))) |
(75) |
b3(a2(b0(x1))) |
→ |
b2(b3(a3(a0(x1)))) |
(79) |
d3(a2(b3(x1))) |
→ |
d2(b3(a3(a3(x1)))) |
(80) |
d3(a2(b1(x1))) |
→ |
d2(b3(a3(a1(x1)))) |
(81) |
d3(a2(b2(x1))) |
→ |
d2(b3(a3(a2(x1)))) |
(82) |
d3(a2(b0(x1))) |
→ |
d2(b3(a3(a0(x1)))) |
(83) |
a0(d0(d3(x1))) |
→ |
a3(a0(d2(b3(x1)))) |
(84) |
a0(d0(d1(x1))) |
→ |
a3(a0(d2(b1(x1)))) |
(85) |
a0(d0(d2(x1))) |
→ |
a3(a0(d2(b2(x1)))) |
(86) |
a0(d0(d0(x1))) |
→ |
a3(a0(d2(b0(x1)))) |
(87) |
c0(d0(d3(x1))) |
→ |
c3(a0(d2(b3(x1)))) |
(88) |
c0(d0(d1(x1))) |
→ |
c3(a0(d2(b1(x1)))) |
(89) |
c0(d0(d2(x1))) |
→ |
c3(a0(d2(b2(x1)))) |
(90) |
c0(d0(d0(x1))) |
→ |
c3(a0(d2(b0(x1)))) |
(91) |
b0(d0(d3(x1))) |
→ |
b3(a0(d2(b3(x1)))) |
(92) |
b0(d0(d1(x1))) |
→ |
b3(a0(d2(b1(x1)))) |
(93) |
b0(d0(d2(x1))) |
→ |
b3(a0(d2(b2(x1)))) |
(94) |
b0(d0(d0(x1))) |
→ |
b3(a0(d2(b0(x1)))) |
(95) |
d0(d0(d3(x1))) |
→ |
d3(a0(d2(b3(x1)))) |
(96) |
d0(d0(d1(x1))) |
→ |
d3(a0(d2(b1(x1)))) |
(97) |
d0(d0(d2(x1))) |
→ |
d3(a0(d2(b2(x1)))) |
(98) |
d0(d0(d0(x1))) |
→ |
d3(a0(d2(b0(x1)))) |
(99) |
a2(b2(b3(x1))) |
→ |
a2(b1(c3(x1))) |
(100) |
a2(b2(b1(x1))) |
→ |
a2(b1(c1(x1))) |
(101) |
a2(b2(b2(x1))) |
→ |
a2(b1(c2(x1))) |
(102) |
a2(b2(b0(x1))) |
→ |
a2(b1(c0(x1))) |
(103) |
c2(b2(b3(x1))) |
→ |
c2(b1(c3(x1))) |
(104) |
c2(b2(b1(x1))) |
→ |
c2(b1(c1(x1))) |
(105) |
c2(b2(b2(x1))) |
→ |
c2(b1(c2(x1))) |
(106) |
c2(b2(b0(x1))) |
→ |
c2(b1(c0(x1))) |
(107) |
b2(b2(b3(x1))) |
→ |
b2(b1(c3(x1))) |
(108) |
b2(b2(b1(x1))) |
→ |
b2(b1(c1(x1))) |
(109) |
b2(b2(b2(x1))) |
→ |
b2(b1(c2(x1))) |
(110) |
b2(b2(b0(x1))) |
→ |
b2(b1(c0(x1))) |
(111) |
d2(b2(b3(x1))) |
→ |
d2(b1(c3(x1))) |
(112) |
d2(b2(b1(x1))) |
→ |
d2(b1(c1(x1))) |
(113) |
d2(b2(b2(x1))) |
→ |
d2(b1(c2(x1))) |
(114) |
d2(b2(b0(x1))) |
→ |
d2(b1(c0(x1))) |
(115) |
a3(a0(d1(c3(x1)))) |
→ |
a1(c3(a3(x1))) |
(116) |
a3(a0(d1(c1(x1)))) |
→ |
a1(c3(a1(x1))) |
(117) |
a3(a0(d1(c2(x1)))) |
→ |
a1(c3(a2(x1))) |
(118) |
a3(a0(d1(c0(x1)))) |
→ |
a1(c3(a0(x1))) |
(119) |
c3(a0(d1(c3(x1)))) |
→ |
c1(c3(a3(x1))) |
(120) |
c3(a0(d1(c1(x1)))) |
→ |
c1(c3(a1(x1))) |
(121) |
c3(a0(d1(c2(x1)))) |
→ |
c1(c3(a2(x1))) |
(122) |
c3(a0(d1(c0(x1)))) |
→ |
c1(c3(a0(x1))) |
(123) |
b3(a0(d1(c3(x1)))) |
→ |
b1(c3(a3(x1))) |
(124) |
b3(a0(d1(c1(x1)))) |
→ |
b1(c3(a1(x1))) |
(125) |
b3(a0(d1(c2(x1)))) |
→ |
b1(c3(a2(x1))) |
(126) |
b3(a0(d1(c0(x1)))) |
→ |
b1(c3(a0(x1))) |
(127) |
d3(a0(d1(c3(x1)))) |
→ |
d1(c3(a3(x1))) |
(128) |
d3(a0(d1(c1(x1)))) |
→ |
d1(c3(a1(x1))) |
(129) |
d3(a0(d1(c2(x1)))) |
→ |
d1(c3(a2(x1))) |
(130) |
d3(a0(d1(c0(x1)))) |
→ |
d1(c3(a0(x1))) |
(131) |
a2(b1(c3(x1))) |
→ |
a3(a3(a3(a3(x1)))) |
(132) |
a2(b1(c1(x1))) |
→ |
a3(a3(a3(a1(x1)))) |
(133) |
a2(b1(c2(x1))) |
→ |
a3(a3(a3(a2(x1)))) |
(134) |
a2(b1(c0(x1))) |
→ |
a3(a3(a3(a0(x1)))) |
(135) |
c2(b1(c3(x1))) |
→ |
c3(a3(a3(a3(x1)))) |
(136) |
c2(b1(c1(x1))) |
→ |
c3(a3(a3(a1(x1)))) |
(137) |
c2(b1(c2(x1))) |
→ |
c3(a3(a3(a2(x1)))) |
(138) |
c2(b1(c0(x1))) |
→ |
c3(a3(a3(a0(x1)))) |
(139) |
b2(b1(c3(x1))) |
→ |
b3(a3(a3(a3(x1)))) |
(140) |
b2(b1(c1(x1))) |
→ |
b3(a3(a3(a1(x1)))) |
(141) |
b2(b1(c2(x1))) |
→ |
b3(a3(a3(a2(x1)))) |
(142) |
b2(b1(c0(x1))) |
→ |
b3(a3(a3(a0(x1)))) |
(143) |
d2(b1(c3(x1))) |
→ |
d3(a3(a3(a3(x1)))) |
(144) |
d2(b1(c1(x1))) |
→ |
d3(a3(a3(a1(x1)))) |
(145) |
d2(b1(c2(x1))) |
→ |
d3(a3(a3(a2(x1)))) |
(146) |
d2(b1(c0(x1))) |
→ |
d3(a3(a3(a0(x1)))) |
(147) |
1.1.1.1 Dependency Pair Transformation
The following set of initial dependency pairs has been identified.
c3#(a1(c3(a1(x1)))) |
→ |
c3#(a1(c1(x1))) |
(148) |
c3#(a1(c3(a3(x1)))) |
→ |
c3#(x1) |
(149) |
c3#(a1(c3(a3(x1)))) |
→ |
c3#(a1(c3(x1))) |
(150) |
b3#(a1(c3(a1(x1)))) |
→ |
c3#(a1(c1(x1))) |
(151) |
b3#(a1(c3(a3(x1)))) |
→ |
c3#(x1) |
(152) |
b3#(a1(c3(a3(x1)))) |
→ |
c3#(a1(c3(x1))) |
(153) |
b3#(a2(b1(x1))) |
→ |
b3#(a3(a1(x1))) |
(154) |
b3#(a2(b1(x1))) |
→ |
a3#(a1(x1)) |
(155) |
b3#(a2(b2(x1))) |
→ |
b3#(a3(a2(x1))) |
(156) |
b3#(a2(b2(x1))) |
→ |
a3#(a2(x1)) |
(157) |
b3#(a2(b3(x1))) |
→ |
b3#(a3(a3(x1))) |
(158) |
b3#(a2(b3(x1))) |
→ |
a3#(x1) |
(159) |
b3#(a2(b3(x1))) |
→ |
a3#(a3(x1)) |
(160) |
a3#(a1(c3(a1(x1)))) |
→ |
c3#(a1(c1(x1))) |
(161) |
a3#(a1(c3(a3(x1)))) |
→ |
c3#(x1) |
(162) |
a3#(a1(c3(a3(x1)))) |
→ |
c3#(a1(c3(x1))) |
(163) |
a3#(a2(b1(x1))) |
→ |
b3#(a3(a1(x1))) |
(164) |
a3#(a2(b1(x1))) |
→ |
a3#(a1(x1)) |
(165) |
a3#(a2(b2(x1))) |
→ |
b3#(a3(a2(x1))) |
(166) |
a3#(a2(b2(x1))) |
→ |
a3#(a2(x1)) |
(167) |
a3#(a2(b3(x1))) |
→ |
b3#(a3(a3(x1))) |
(168) |
a3#(a2(b3(x1))) |
→ |
a3#(x1) |
(169) |
a3#(a2(b3(x1))) |
→ |
a3#(a3(x1)) |
(170) |
1.1.1.1.1 Monotonic Reduction Pair Processor with Usable Rules
Using the matrix interpretations of dimension 1 with strict dimension 1 over the rationals with delta = 1
[c1(x1)] |
= |
x1 +
|
[c3(x1)] |
= |
x1 +
|
[b1(x1)] |
= |
x1 +
|
[b2(x1)] |
= |
x1 +
|
[b3(x1)] |
= |
x1 +
|
[a1(x1)] |
= |
x1 +
|
[a2(x1)] |
= |
x1 +
|
[a3(x1)] |
= |
x1 +
|
[c3#(x1)] |
= |
x1 +
|
[b3#(x1)] |
= |
x1 +
|
[a3#(x1)] |
= |
x1 +
|
together with the usable
rules
a3(a1(c3(a3(x1)))) |
→ |
a1(c3(a1(c3(x1)))) |
(36) |
a3(a1(c3(a1(x1)))) |
→ |
a1(c3(a1(c1(x1)))) |
(37) |
c3(a1(c3(a3(x1)))) |
→ |
c1(c3(a1(c3(x1)))) |
(40) |
c3(a1(c3(a1(x1)))) |
→ |
c1(c3(a1(c1(x1)))) |
(41) |
b3(a1(c3(a3(x1)))) |
→ |
b1(c3(a1(c3(x1)))) |
(44) |
b3(a1(c3(a1(x1)))) |
→ |
b1(c3(a1(c1(x1)))) |
(45) |
a3(a2(b3(x1))) |
→ |
a2(b3(a3(a3(x1)))) |
(68) |
a3(a2(b1(x1))) |
→ |
a2(b3(a3(a1(x1)))) |
(69) |
a3(a2(b2(x1))) |
→ |
a2(b3(a3(a2(x1)))) |
(70) |
b3(a2(b3(x1))) |
→ |
b2(b3(a3(a3(x1)))) |
(76) |
b3(a2(b1(x1))) |
→ |
b2(b3(a3(a1(x1)))) |
(77) |
b3(a2(b2(x1))) |
→ |
b2(b3(a3(a2(x1)))) |
(78) |
(w.r.t. the implicit argument filter of the reduction pair),
the
pairs
b3#(a1(c3(a1(x1)))) |
→ |
c3#(a1(c1(x1))) |
(151) |
b3#(a1(c3(a3(x1)))) |
→ |
c3#(x1) |
(152) |
b3#(a1(c3(a3(x1)))) |
→ |
c3#(a1(c3(x1))) |
(153) |
b3#(a2(b1(x1))) |
→ |
b3#(a3(a1(x1))) |
(154) |
b3#(a2(b1(x1))) |
→ |
a3#(a1(x1)) |
(155) |
b3#(a2(b2(x1))) |
→ |
b3#(a3(a2(x1))) |
(156) |
b3#(a2(b2(x1))) |
→ |
a3#(a2(x1)) |
(157) |
b3#(a2(b3(x1))) |
→ |
b3#(a3(a3(x1))) |
(158) |
b3#(a2(b3(x1))) |
→ |
a3#(x1) |
(159) |
b3#(a2(b3(x1))) |
→ |
a3#(a3(x1)) |
(160) |
a3#(a1(c3(a1(x1)))) |
→ |
c3#(a1(c1(x1))) |
(161) |
a3#(a1(c3(a3(x1)))) |
→ |
c3#(x1) |
(162) |
a3#(a1(c3(a3(x1)))) |
→ |
c3#(a1(c3(x1))) |
(163) |
a3#(a2(b1(x1))) |
→ |
b3#(a3(a1(x1))) |
(164) |
a3#(a2(b1(x1))) |
→ |
a3#(a1(x1)) |
(165) |
a3#(a2(b2(x1))) |
→ |
b3#(a3(a2(x1))) |
(166) |
a3#(a2(b2(x1))) |
→ |
a3#(a2(x1)) |
(167) |
a3#(a2(b3(x1))) |
→ |
b3#(a3(a3(x1))) |
(168) |
a3#(a2(b3(x1))) |
→ |
a3#(x1) |
(169) |
a3#(a2(b3(x1))) |
→ |
a3#(a3(x1)) |
(170) |
and
no rules
could be deleted.
1.1.1.1.1.1 Dependency Graph Processor
The dependency pairs are split into 1
component.