Certification Problem
Input (TPDB SRS_Standard/Zantema_04/z083)
The rewrite relation of the following TRS is considered.
b(d(b(x1))) |
→ |
c(d(b(x1))) |
(1) |
b(a(c(x1))) |
→ |
b(c(x1)) |
(2) |
a(d(x1)) |
→ |
d(c(x1)) |
(3) |
b(b(b(x1))) |
→ |
a(b(c(x1))) |
(4) |
d(c(x1)) |
→ |
b(d(x1)) |
(5) |
d(c(x1)) |
→ |
d(b(d(x1))) |
(6) |
d(a(c(x1))) |
→ |
b(b(x1)) |
(7) |
Property / Task
Prove or disprove termination.Answer / Result
Yes.Proof (by matchbox @ termCOMP 2023)
1 Rule Removal
Using the
matrix interpretations of dimension 1 with strict dimension 1 over the rationals with delta = 1
[d(x1)] |
= |
x1 +
|
[c(x1)] |
= |
x1 +
|
[b(x1)] |
= |
x1 +
|
[a(x1)] |
= |
x1 +
|
all of the following rules can be deleted.
b(a(c(x1))) |
→ |
b(c(x1)) |
(2) |
1.1 Split
We split R in the relative problem D/R-D and R-D, where the rules D
a(d(x1)) |
→ |
d(c(x1)) |
(3) |
b(b(b(x1))) |
→ |
a(b(c(x1))) |
(4) |
d(c(x1)) |
→ |
d(b(d(x1))) |
(6) |
d(a(c(x1))) |
→ |
b(b(x1)) |
(7) |
are deleted.
1.1.1 Closure Under Flat Contexts
Using the flat contexts
{d(☐), c(☐), b(☐), a(☐)}
We obtain the transformed TRS
d(a(d(x1))) |
→ |
d(d(c(x1))) |
(8) |
d(b(b(b(x1)))) |
→ |
d(a(b(c(x1)))) |
(9) |
d(d(c(x1))) |
→ |
d(d(b(d(x1)))) |
(10) |
d(d(a(c(x1)))) |
→ |
d(b(b(x1))) |
(11) |
c(a(d(x1))) |
→ |
c(d(c(x1))) |
(12) |
c(b(b(b(x1)))) |
→ |
c(a(b(c(x1)))) |
(13) |
c(d(c(x1))) |
→ |
c(d(b(d(x1)))) |
(14) |
c(d(a(c(x1)))) |
→ |
c(b(b(x1))) |
(15) |
b(a(d(x1))) |
→ |
b(d(c(x1))) |
(16) |
b(b(b(b(x1)))) |
→ |
b(a(b(c(x1)))) |
(17) |
b(d(c(x1))) |
→ |
b(d(b(d(x1)))) |
(18) |
b(d(a(c(x1)))) |
→ |
b(b(b(x1))) |
(19) |
a(a(d(x1))) |
→ |
a(d(c(x1))) |
(20) |
a(b(b(b(x1)))) |
→ |
a(a(b(c(x1)))) |
(21) |
a(d(c(x1))) |
→ |
a(d(b(d(x1)))) |
(22) |
a(d(a(c(x1)))) |
→ |
a(b(b(x1))) |
(23) |
d(b(d(b(x1)))) |
→ |
d(c(d(b(x1)))) |
(24) |
d(d(c(x1))) |
→ |
d(b(d(x1))) |
(25) |
c(b(d(b(x1)))) |
→ |
c(c(d(b(x1)))) |
(26) |
c(d(c(x1))) |
→ |
c(b(d(x1))) |
(27) |
b(b(d(b(x1)))) |
→ |
b(c(d(b(x1)))) |
(28) |
b(d(c(x1))) |
→ |
b(b(d(x1))) |
(29) |
a(b(d(b(x1)))) |
→ |
a(c(d(b(x1)))) |
(30) |
a(d(c(x1))) |
→ |
a(b(d(x1))) |
(31) |
1.1.1.1 Closure Under Flat Contexts
Using the flat contexts
{d(☐), c(☐), b(☐), a(☐)}
We obtain the transformed TRS
d(d(a(d(x1)))) |
→ |
d(d(d(c(x1)))) |
(32) |
d(d(b(b(b(x1))))) |
→ |
d(d(a(b(c(x1))))) |
(33) |
d(d(d(c(x1)))) |
→ |
d(d(d(b(d(x1))))) |
(34) |
d(d(d(a(c(x1))))) |
→ |
d(d(b(b(x1)))) |
(35) |
d(c(a(d(x1)))) |
→ |
d(c(d(c(x1)))) |
(36) |
d(c(b(b(b(x1))))) |
→ |
d(c(a(b(c(x1))))) |
(37) |
d(c(d(c(x1)))) |
→ |
d(c(d(b(d(x1))))) |
(38) |
d(c(d(a(c(x1))))) |
→ |
d(c(b(b(x1)))) |
(39) |
d(b(a(d(x1)))) |
→ |
d(b(d(c(x1)))) |
(40) |
d(b(b(b(b(x1))))) |
→ |
d(b(a(b(c(x1))))) |
(41) |
d(b(d(c(x1)))) |
→ |
d(b(d(b(d(x1))))) |
(42) |
d(b(d(a(c(x1))))) |
→ |
d(b(b(b(x1)))) |
(43) |
d(a(a(d(x1)))) |
→ |
d(a(d(c(x1)))) |
(44) |
d(a(b(b(b(x1))))) |
→ |
d(a(a(b(c(x1))))) |
(45) |
d(a(d(c(x1)))) |
→ |
d(a(d(b(d(x1))))) |
(46) |
d(a(d(a(c(x1))))) |
→ |
d(a(b(b(x1)))) |
(47) |
c(d(a(d(x1)))) |
→ |
c(d(d(c(x1)))) |
(48) |
c(d(b(b(b(x1))))) |
→ |
c(d(a(b(c(x1))))) |
(49) |
c(d(d(c(x1)))) |
→ |
c(d(d(b(d(x1))))) |
(50) |
c(d(d(a(c(x1))))) |
→ |
c(d(b(b(x1)))) |
(51) |
c(c(a(d(x1)))) |
→ |
c(c(d(c(x1)))) |
(52) |
c(c(b(b(b(x1))))) |
→ |
c(c(a(b(c(x1))))) |
(53) |
c(c(d(c(x1)))) |
→ |
c(c(d(b(d(x1))))) |
(54) |
c(c(d(a(c(x1))))) |
→ |
c(c(b(b(x1)))) |
(55) |
c(b(a(d(x1)))) |
→ |
c(b(d(c(x1)))) |
(56) |
c(b(b(b(b(x1))))) |
→ |
c(b(a(b(c(x1))))) |
(57) |
c(b(d(c(x1)))) |
→ |
c(b(d(b(d(x1))))) |
(58) |
c(b(d(a(c(x1))))) |
→ |
c(b(b(b(x1)))) |
(59) |
c(a(a(d(x1)))) |
→ |
c(a(d(c(x1)))) |
(60) |
c(a(b(b(b(x1))))) |
→ |
c(a(a(b(c(x1))))) |
(61) |
c(a(d(c(x1)))) |
→ |
c(a(d(b(d(x1))))) |
(62) |
c(a(d(a(c(x1))))) |
→ |
c(a(b(b(x1)))) |
(63) |
b(d(a(d(x1)))) |
→ |
b(d(d(c(x1)))) |
(64) |
b(d(b(b(b(x1))))) |
→ |
b(d(a(b(c(x1))))) |
(65) |
b(d(d(c(x1)))) |
→ |
b(d(d(b(d(x1))))) |
(66) |
b(d(d(a(c(x1))))) |
→ |
b(d(b(b(x1)))) |
(67) |
b(c(a(d(x1)))) |
→ |
b(c(d(c(x1)))) |
(68) |
b(c(b(b(b(x1))))) |
→ |
b(c(a(b(c(x1))))) |
(69) |
b(c(d(c(x1)))) |
→ |
b(c(d(b(d(x1))))) |
(70) |
b(c(d(a(c(x1))))) |
→ |
b(c(b(b(x1)))) |
(71) |
b(b(a(d(x1)))) |
→ |
b(b(d(c(x1)))) |
(72) |
b(b(b(b(b(x1))))) |
→ |
b(b(a(b(c(x1))))) |
(73) |
b(b(d(c(x1)))) |
→ |
b(b(d(b(d(x1))))) |
(74) |
b(b(d(a(c(x1))))) |
→ |
b(b(b(b(x1)))) |
(75) |
b(a(a(d(x1)))) |
→ |
b(a(d(c(x1)))) |
(76) |
b(a(b(b(b(x1))))) |
→ |
b(a(a(b(c(x1))))) |
(77) |
b(a(d(c(x1)))) |
→ |
b(a(d(b(d(x1))))) |
(78) |
b(a(d(a(c(x1))))) |
→ |
b(a(b(b(x1)))) |
(79) |
a(d(a(d(x1)))) |
→ |
a(d(d(c(x1)))) |
(80) |
a(d(b(b(b(x1))))) |
→ |
a(d(a(b(c(x1))))) |
(81) |
a(d(d(c(x1)))) |
→ |
a(d(d(b(d(x1))))) |
(82) |
a(d(d(a(c(x1))))) |
→ |
a(d(b(b(x1)))) |
(83) |
a(c(a(d(x1)))) |
→ |
a(c(d(c(x1)))) |
(84) |
a(c(b(b(b(x1))))) |
→ |
a(c(a(b(c(x1))))) |
(85) |
a(c(d(c(x1)))) |
→ |
a(c(d(b(d(x1))))) |
(86) |
a(c(d(a(c(x1))))) |
→ |
a(c(b(b(x1)))) |
(87) |
a(b(a(d(x1)))) |
→ |
a(b(d(c(x1)))) |
(88) |
a(b(b(b(b(x1))))) |
→ |
a(b(a(b(c(x1))))) |
(89) |
a(b(d(c(x1)))) |
→ |
a(b(d(b(d(x1))))) |
(90) |
a(b(d(a(c(x1))))) |
→ |
a(b(b(b(x1)))) |
(91) |
a(a(a(d(x1)))) |
→ |
a(a(d(c(x1)))) |
(92) |
a(a(b(b(b(x1))))) |
→ |
a(a(a(b(c(x1))))) |
(93) |
a(a(d(c(x1)))) |
→ |
a(a(d(b(d(x1))))) |
(94) |
a(a(d(a(c(x1))))) |
→ |
a(a(b(b(x1)))) |
(95) |
d(d(b(d(b(x1))))) |
→ |
d(d(c(d(b(x1))))) |
(96) |
d(d(d(c(x1)))) |
→ |
d(d(b(d(x1)))) |
(97) |
d(c(b(d(b(x1))))) |
→ |
d(c(c(d(b(x1))))) |
(98) |
d(c(d(c(x1)))) |
→ |
d(c(b(d(x1)))) |
(99) |
d(b(b(d(b(x1))))) |
→ |
d(b(c(d(b(x1))))) |
(100) |
d(b(d(c(x1)))) |
→ |
d(b(b(d(x1)))) |
(101) |
d(a(b(d(b(x1))))) |
→ |
d(a(c(d(b(x1))))) |
(102) |
d(a(d(c(x1)))) |
→ |
d(a(b(d(x1)))) |
(103) |
c(d(b(d(b(x1))))) |
→ |
c(d(c(d(b(x1))))) |
(104) |
c(d(d(c(x1)))) |
→ |
c(d(b(d(x1)))) |
(105) |
c(c(b(d(b(x1))))) |
→ |
c(c(c(d(b(x1))))) |
(106) |
c(c(d(c(x1)))) |
→ |
c(c(b(d(x1)))) |
(107) |
c(b(b(d(b(x1))))) |
→ |
c(b(c(d(b(x1))))) |
(108) |
c(b(d(c(x1)))) |
→ |
c(b(b(d(x1)))) |
(109) |
c(a(b(d(b(x1))))) |
→ |
c(a(c(d(b(x1))))) |
(110) |
c(a(d(c(x1)))) |
→ |
c(a(b(d(x1)))) |
(111) |
b(d(b(d(b(x1))))) |
→ |
b(d(c(d(b(x1))))) |
(112) |
b(d(d(c(x1)))) |
→ |
b(d(b(d(x1)))) |
(113) |
b(c(b(d(b(x1))))) |
→ |
b(c(c(d(b(x1))))) |
(114) |
b(c(d(c(x1)))) |
→ |
b(c(b(d(x1)))) |
(115) |
b(b(b(d(b(x1))))) |
→ |
b(b(c(d(b(x1))))) |
(116) |
b(b(d(c(x1)))) |
→ |
b(b(b(d(x1)))) |
(117) |
b(a(b(d(b(x1))))) |
→ |
b(a(c(d(b(x1))))) |
(118) |
b(a(d(c(x1)))) |
→ |
b(a(b(d(x1)))) |
(119) |
a(d(b(d(b(x1))))) |
→ |
a(d(c(d(b(x1))))) |
(120) |
a(d(d(c(x1)))) |
→ |
a(d(b(d(x1)))) |
(121) |
a(c(b(d(b(x1))))) |
→ |
a(c(c(d(b(x1))))) |
(122) |
a(c(d(c(x1)))) |
→ |
a(c(b(d(x1)))) |
(123) |
a(b(b(d(b(x1))))) |
→ |
a(b(c(d(b(x1))))) |
(124) |
a(b(d(c(x1)))) |
→ |
a(b(b(d(x1)))) |
(125) |
a(a(b(d(b(x1))))) |
→ |
a(a(c(d(b(x1))))) |
(126) |
a(a(d(c(x1)))) |
→ |
a(a(b(d(x1)))) |
(127) |
1.1.1.1.1 Semantic Labeling
The following interpretations form a
model
of the rules.
As carrier we take the set
{0,...,15}.
Symbols are labeled by the interpretation of their arguments using the interpretations
(modulo 16):
[d(x1)] |
= |
4x1 + 0 |
[c(x1)] |
= |
4x1 + 1 |
[b(x1)] |
= |
4x1 + 2 |
[a(x1)] |
= |
4x1 + 3 |
We obtain the labeled TRS
There are 1536 ruless (increase limit for explicit display).
1.1.1.1.1.1 Rule Removal
Using the
matrix interpretations of dimension 1 with strict dimension 1 over the rationals with delta = 1
[d0(x1)] |
= |
x1 +
|
[d4(x1)] |
= |
x1 +
|
[d8(x1)] |
= |
x1 +
|
[d12(x1)] |
= |
x1 +
|
[d1(x1)] |
= |
x1 +
|
[d5(x1)] |
= |
x1 +
|
[d9(x1)] |
= |
x1 +
|
[d13(x1)] |
= |
x1 +
|
[d2(x1)] |
= |
x1 +
|
[d6(x1)] |
= |
x1 +
|
[d10(x1)] |
= |
x1 +
|
[d14(x1)] |
= |
x1 +
|
[d3(x1)] |
= |
x1 +
|
[d7(x1)] |
= |
x1 +
|
[d11(x1)] |
= |
x1 +
|
[d15(x1)] |
= |
x1 +
|
[c0(x1)] |
= |
x1 +
|
[c4(x1)] |
= |
x1 +
|
[c8(x1)] |
= |
x1 +
|
[c12(x1)] |
= |
x1 +
|
[c1(x1)] |
= |
x1 +
|
[c5(x1)] |
= |
x1 +
|
[c9(x1)] |
= |
x1 +
|
[c13(x1)] |
= |
x1 +
|
[c2(x1)] |
= |
x1 +
|
[c6(x1)] |
= |
x1 +
|
[c10(x1)] |
= |
x1 +
|
[c14(x1)] |
= |
x1 +
|
[c3(x1)] |
= |
x1 +
|
[c7(x1)] |
= |
x1 +
|
[c11(x1)] |
= |
x1 +
|
[c15(x1)] |
= |
x1 +
|
[b0(x1)] |
= |
x1 +
|
[b4(x1)] |
= |
x1 +
|
[b8(x1)] |
= |
x1 +
|
[b12(x1)] |
= |
x1 +
|
[b1(x1)] |
= |
x1 +
|
[b5(x1)] |
= |
x1 +
|
[b9(x1)] |
= |
x1 +
|
[b13(x1)] |
= |
x1 +
|
[b2(x1)] |
= |
x1 +
|
[b6(x1)] |
= |
x1 +
|
[b10(x1)] |
= |
x1 +
|
[b14(x1)] |
= |
x1 +
|
[b3(x1)] |
= |
x1 +
|
[b7(x1)] |
= |
x1 +
|
[b11(x1)] |
= |
x1 +
|
[b15(x1)] |
= |
x1 +
|
[a0(x1)] |
= |
x1 +
|
[a4(x1)] |
= |
x1 +
|
[a8(x1)] |
= |
x1 +
|
[a12(x1)] |
= |
x1 +
|
[a1(x1)] |
= |
x1 +
|
[a5(x1)] |
= |
x1 +
|
[a9(x1)] |
= |
x1 +
|
[a13(x1)] |
= |
x1 +
|
[a2(x1)] |
= |
x1 +
|
[a6(x1)] |
= |
x1 +
|
[a10(x1)] |
= |
x1 +
|
[a14(x1)] |
= |
x1 +
|
[a3(x1)] |
= |
x1 +
|
[a7(x1)] |
= |
x1 +
|
[a11(x1)] |
= |
x1 +
|
[a15(x1)] |
= |
x1 +
|
all of the following rules can be deleted.
There are 1498 ruless (increase limit for explicit display).
1.1.1.1.1.1.1 R is empty
There are no rules in the TRS. Hence, it is terminating.
1.1.2 Closure Under Flat Contexts
Using the flat contexts
{d(☐), c(☐), b(☐)}
We obtain the transformed TRS
d(b(d(b(x1)))) |
→ |
d(c(d(b(x1)))) |
(24) |
d(d(c(x1))) |
→ |
d(b(d(x1))) |
(25) |
c(b(d(b(x1)))) |
→ |
c(c(d(b(x1)))) |
(26) |
c(d(c(x1))) |
→ |
c(b(d(x1))) |
(27) |
b(b(d(b(x1)))) |
→ |
b(c(d(b(x1)))) |
(28) |
b(d(c(x1))) |
→ |
b(b(d(x1))) |
(29) |
1.1.2.1 Semantic Labeling
The following interpretations form a
model
of the rules.
As carrier we take the set
{0,1,2}.
Symbols are labeled by the interpretation of their arguments using the interpretations
(modulo 3):
[d(x1)] |
= |
3x1 + 0 |
[c(x1)] |
= |
3x1 + 1 |
[b(x1)] |
= |
3x1 + 2 |
We obtain the labeled TRS
b2(b0(d2(b2(x1)))) |
→ |
b1(c0(d2(b2(x1)))) |
(1664) |
b2(b0(d2(b0(x1)))) |
→ |
b1(c0(d2(b0(x1)))) |
(1665) |
b2(b0(d2(b1(x1)))) |
→ |
b1(c0(d2(b1(x1)))) |
(1666) |
d2(b0(d2(b2(x1)))) |
→ |
d1(c0(d2(b2(x1)))) |
(1667) |
d2(b0(d2(b0(x1)))) |
→ |
d1(c0(d2(b0(x1)))) |
(1668) |
d2(b0(d2(b1(x1)))) |
→ |
d1(c0(d2(b1(x1)))) |
(1669) |
c2(b0(d2(b2(x1)))) |
→ |
c1(c0(d2(b2(x1)))) |
(1670) |
c2(b0(d2(b0(x1)))) |
→ |
c1(c0(d2(b0(x1)))) |
(1671) |
c2(b0(d2(b1(x1)))) |
→ |
c1(c0(d2(b1(x1)))) |
(1672) |
b0(d1(c2(x1))) |
→ |
b2(b0(d2(x1))) |
(1673) |
b0(d1(c0(x1))) |
→ |
b2(b0(d0(x1))) |
(1674) |
b0(d1(c1(x1))) |
→ |
b2(b0(d1(x1))) |
(1675) |
d0(d1(c2(x1))) |
→ |
d2(b0(d2(x1))) |
(1676) |
d0(d1(c0(x1))) |
→ |
d2(b0(d0(x1))) |
(1677) |
d0(d1(c1(x1))) |
→ |
d2(b0(d1(x1))) |
(1678) |
c0(d1(c2(x1))) |
→ |
c2(b0(d2(x1))) |
(1679) |
c0(d1(c0(x1))) |
→ |
c2(b0(d0(x1))) |
(1680) |
c0(d1(c1(x1))) |
→ |
c2(b0(d1(x1))) |
(1681) |
1.1.2.1.1 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 +
|
[c0(x1)] |
= |
x1 +
|
[c1(x1)] |
= |
x1 +
|
[c2(x1)] |
= |
x1 +
|
[b0(x1)] |
= |
x1 +
|
[b1(x1)] |
= |
x1 +
|
[b2(x1)] |
= |
x1 +
|
all of the following rules can be deleted.
b2(b0(d2(b2(x1)))) |
→ |
b1(c0(d2(b2(x1)))) |
(1664) |
b2(b0(d2(b0(x1)))) |
→ |
b1(c0(d2(b0(x1)))) |
(1665) |
b2(b0(d2(b1(x1)))) |
→ |
b1(c0(d2(b1(x1)))) |
(1666) |
b0(d1(c2(x1))) |
→ |
b2(b0(d2(x1))) |
(1673) |
b0(d1(c0(x1))) |
→ |
b2(b0(d0(x1))) |
(1674) |
b0(d1(c1(x1))) |
→ |
b2(b0(d1(x1))) |
(1675) |
1.1.2.1.1.1 Rule Removal
Using the
matrix interpretations of dimension 1 with strict dimension 1 over the naturals
[d0(x1)] |
= |
· x1 +
|
[d1(x1)] |
= |
· x1 +
|
[d2(x1)] |
= |
· x1 +
|
[c0(x1)] |
= |
· x1 +
|
[c1(x1)] |
= |
· x1 +
|
[c2(x1)] |
= |
· x1 +
|
[b0(x1)] |
= |
· x1 +
|
[b1(x1)] |
= |
· x1 +
|
[b2(x1)] |
= |
· x1 +
|
all of the following rules can be deleted.
d2(b0(d2(b2(x1)))) |
→ |
d1(c0(d2(b2(x1)))) |
(1667) |
d2(b0(d2(b0(x1)))) |
→ |
d1(c0(d2(b0(x1)))) |
(1668) |
d2(b0(d2(b1(x1)))) |
→ |
d1(c0(d2(b1(x1)))) |
(1669) |
c2(b0(d2(b2(x1)))) |
→ |
c1(c0(d2(b2(x1)))) |
(1670) |
c2(b0(d2(b0(x1)))) |
→ |
c1(c0(d2(b0(x1)))) |
(1671) |
c2(b0(d2(b1(x1)))) |
→ |
c1(c0(d2(b1(x1)))) |
(1672) |
1.1.2.1.1.1.1 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 +
|
[c0(x1)] |
= |
x1 +
|
[c1(x1)] |
= |
x1 +
|
[c2(x1)] |
= |
x1 +
|
[b0(x1)] |
= |
x1 +
|
all of the following rules can be deleted.
d0(d1(c2(x1))) |
→ |
d2(b0(d2(x1))) |
(1676) |
d0(d1(c0(x1))) |
→ |
d2(b0(d0(x1))) |
(1677) |
d0(d1(c1(x1))) |
→ |
d2(b0(d1(x1))) |
(1678) |
c0(d1(c2(x1))) |
→ |
c2(b0(d2(x1))) |
(1679) |
c0(d1(c0(x1))) |
→ |
c2(b0(d0(x1))) |
(1680) |
c0(d1(c1(x1))) |
→ |
c2(b0(d1(x1))) |
(1681) |
1.1.2.1.1.1.1.1 R is empty
There are no rules in the TRS. Hence, it is terminating.