Research Article

New Bounds for Ternary Covering Arrays Using a Parallel Simulated Annealing

Table 2

It shows the improved bounds produced by CSA approach. Column 𝜗 represents the best-known solution reported in the literature [30]. Column 𝛽 represents the best solution in terms of 𝑁 produced by CSA approach. Last column ( Δ ) depicts the difference between the best result produced by CSA approach and the best-known solution ( Δ = 𝛽 𝜗 ). (a) Improved bounds on C A N ( 3 , 𝑘 , 3 ) ; (b) improved bounds on C A N ( 4 , 𝑘 , 3 ) ; (c) improved bounds on C A N ( 5 , 𝑘 , 3 ) ; (d) improved bounds on C A N ( 6 , 𝑘 , 3 ) .
(a)

𝑡 𝑘 𝜗 𝛽 Δ

3 4 27 27 0
3 5 33 33 0
3 6 33 33 0
3 7 40 39 −1
3 8 42 42 0
3 9 45 45 0
3 10 45 45 0
3 11 45 45 0
3 12 45 45 0
3 13 50 49 −1
3 14 51 50 −1
3 15 57 57 0
3 16 60 59 −1
3 17 60 59 −1
3 18 60 59 −1
3 19 60 59 −1
3 20 60 59 −1
3 21 66 67 1
3 22 66 71 5
3 23 69 71 2
3 24 72 71 −1
3 25 75 72 −3
3 26 78 72 −6
3 27 81 79 −2
3 28 81 79 −2
3 29 87 84 −3
3 30 87 84 −3
3 31 90 88 −2
3 32 90 89 −1
3 33 90 89 −1
3 34 90 89 −1
3 35 90 89 −1
3 36 90 89 −1
3 37 90 89 −1
3 38 90 89 −1
3 39 90 89 −1
3 40 90 89 −1
3 41 98 94 −4
3 42 98 94 −4
3 43 100 99 −1
3 44 100 99 −1
3 45 103 99 −4
3 46 103 101 −2
3 47 106 101 −5
3 48 106 101 −5
3 49 108 101 −7
3 50 108 102 −6

(b)

𝑡 𝑘 𝜗 𝛽 Δ

4 5 81 81 0
4 6 111 111 0
4 7 123 123 0
4 8 141 135 −6
4 9 159 135 −24
4 10 159 164 5
4 11 183 183 0
4 12 201 201 0
4 13 219 219 0
4 14 237 249 12
4 15 237 277 40
4 16 237 277 40
4 17 300 287 −13
4 18 307 300 −7
4 19 313 313 0
4 20 315 321 6
4 21 315 338 23
4 22 315 347 32
4 23 315 359 44
4 24 377 375 −2
4 25 384 375 −9
4 26 393 387 −6
4 27 393 387 −6
4 28 393 392 −1
4 29 393 406 13
4 30 393 401 8
4 31 440 424 −16
4 32 445 431 −14
4 33 454 438 −16
4 34 462 447 −15
4 35 471 440 −31
4 36 471 456 −15
4 37 471 460 −11
4 38 471 465 −6
4 39 471 468 −3
4 40 499 472 −27
4 41 506 484 −22
4 42 509 488 −21
4 43 518 494 −24
4 44 522 497 −25
4 45 526 497 −29
4 46 530 506 −24
4 47 534 510 −24
4 48 542 516 −26
4 49 549 523 −26
4 50 549 525 −24

(c)

𝑡 𝑘 𝜗 𝛽 Δ

5 6 243 243 0
5 7 351 351 0
5 8 405 405 0
5 9 483 405 −78
5 10 483 405 −78
5 11 705 550 −155
5 12 723 600 −123
5 13 723 828 105
5 14 922 890 −32
5 15 963 944 −19
5 16 963 1025 62
5 17 1117 1117 0
5 18 1167 1165 −2
5 19 1197 1190 −7
5 20 1266 1257 −9
5 21 1317 1312 −5
5 22 1346 1319 −27
5 23 1405 1387 −18
5 24 1447 1420 −27
5 25 1486 1440 −46
5 26 1521 1493 −28
5 27 1538 1527 −11
5 28 1579 1555 −24
5 29 1615 1585 −30
5 30 1647 1616 −31
5 31 1681 1643 −38
5 32 1724 1671 −53
5 33 1783 1702 −81
5 34 1783 1724 −59
5 35 1851 1748 −103
5 36 1882 1778 −104
5 37 1909 1800 −109
5 38 1937 1829 −108
5 39 1960 1851 −109
5 40 1986 1866 −120
5 41 2023 1896 −127
5 42 2046 1923 −123
5 43 2069 1940 −129
5 44 2091 2089 −2
5 45 2112 2111 −1
5 46 2130 2129 −1
5 47 2150 2149 −1
5 48 2174 2168 −6
5 49 2191 2189 −2
5 50 2213 2211 −2

(d)

𝑡 𝑘 𝜗 𝛽 Δ

6 7 729 729 0
6 8 1152 1152 0
6 9 1431 1600 169
6 10 1449 1849 400
6 11 1449 2136 687
6 12 2181 2482 301
6 13 2734 2744 10
6 14 2907 3220 313
6 15 3234 3338 104
6 16 3443 3672 229
6 17 3658 3882 224
6 18 3846 4098 252
6 19 4054 4256 202
6 20 4486 4400 −86
6 21 4678 4600 −78
6 22 4853 4732 −121
6 23 4942 4941 −1
6 24 5193 5100 −93
6 25 5257 5238 −19
6 26 5709 5380 −329
6 27 5853 5810 −43
6 28 6003 5965 −38
6 29 6150 6110 −40
6 30 6281 6250 −31
6 31 6413 6393 −20
6 32 6535 6518 −17
6 33 6656 6642 −14
6 34 6772 6760 −12
6 35 6877 6871 −6
6 36 6989 6978 −11
6 37 7092 7086 −6
6 38 7194 7187 −7
6 39 7293 7284 −9
6 40 7391 7385 −6
6 41 7490 7478 −12
6 42 7574 7569 −5
6 43 7672 7661 −11
6 44 7757 7748 −9
6 45 7845 7836 −9
6 46 7938 7928 −10
6 47 8013 8005 −8
6 48 8092 8089 −3
6 49 8179 8176 −3
6 50 8256 8253 −3