The tables currently have 9126 entries from 86 different contributors


last updated at 2020-05-20 17:22:34

Top Contributors

LJCR 3868
Jan de Heer and Steve Muir 3046
Enzo Franzese 431
Colin Barker 321
Michael Dambmann 190
Terenzio Lazzarotto 173
Anastasios Tampakis 111
Tommaso Tanto 81
Kamal Fadlaoui 73
Flavio Perona 63
Pio Leonardi 55
Alessandro Jurcovich 54
Marco Meoli 45
Jan de Heer 45
Sveta Marjanovic 39
Dietmar Pree 37
Mathias Liesener 34
E. Franzese, A. Jurcovich E M. Meoli 34
Rade Belic 29
Kleszek 26
Kinski and Genivaldo Pereira 25
Barnabas Toth 25
Jiang Yong Ming and Jiang Kun Xi 24
Andrei Ochmat 23
Chaoying Dai, Ben Li and Michel Toulouse 21
Jiang Yong Ming 20
Felix Rodriguez Martin 19
Luciano Rezende 18
777ch 16
Rade Belic and Dragan Stojiljkovic 14
Adolf Muehl 13
Vinicius Alves 12
Rade Belic and Jan de Heer 12
Aline Marie Menezes Wanderlei 11
A. Jurcovich, M. Meoli E E. Franzese 11
Gerald Unger 9
Alessandro Jurcovich E Marco Meoli 8
Karsten Schölzel 6
W.h.mills and R.c.mullin 5
Roy Gourgi 5
W.h.mills 4
Jan de Heer and Rade Belic 4
Enzo Franzese E Marco Meoli 4
Antonio Franzese 4
Stefano de Martino 3
Marco Meoli-alessandro Jurcovich-enzo Franzese 3
Daryl Burns 3
Sveta Marjanovicandanastasios Tampakis 2
Sveta Marjanovic and Anastasios Tampakis 2
Steve Muir 2
Mario Pina 2
Marco Meoli E Alessandro Jurcovich 2
Iliya Bluskov 2
Guenther Schlegl 2
Fair_play 2
Claus Friis 2
Bluskov and Hamalainen 2
Weber Azevedo E Enzo Franzese 1
W. H. Mills 1
Tung Le 1
Riccardo Bertolo and Jan de Heer 1
Riccardo Bertolo and Francesco Santisi 1
Rade Belic and Dietmar Pree 1
Namyk Kemal Erdogan 1
Marco Meoli Alessandro Jurcovich 1
Kinsky and Genivaldo Pereira 1
Karsten Scholzel 1
Jose Milan Vega 1
Jaera 1
Igor Lazebnik 1
Enzo Franzese E Terenzio Lazzarotto 1
Enzo Franzese E Michael Dambmann 1
Enzo Franzese E Flavio Perona 1
Enzo Franzese E Dietmar Pree 1
Enzo Franzese E Alessandro Jurcovich 1
Dietmar Pree and Rade Belic 1
Dietmar Pree and Adolf Muehl 1
Chaoying Dai, Ben Li and Michel Toulouse, Reduced By Rade Belic 1
Carmine Iorio 1
Bigmax 1
Anastasios Tampakis and Sveta Marjanovic 1
Alexandre Spaeth 1
Alessandro Jurcovich E Enzo Franzese 1
Adolf Muehl and Dietmar Pree 1
A. Tampakis and A. Jurchovich 1
A. Betten, R. Laue and A. Wassermann 1





Overall there have been 75106 entries from 168 different contributors

All-time Contributors






LJCR 50133
Jan de Heer and Steve Muir 5974
Michael Dambmann 2254
Enzo Franzese 2192
Tommaso Tanto 1799
Terenzio Lazzarotto 1710
JCD Article 1632
Flavio Perona 1532
Rade Belic 1441
Rade Belic and Dragan Stojiljkovic 539
Colin Barker 457
Gerald Unger 343
E. Franzese, A. Jurcovich E M. Meoli 324
Anastasios Tampakis 318
Alessandro Jurcovich 290
Kinski and Genivaldo Pereira 278
Jiang Yong Ming and Jiang Kun Xi 270
Marco Meoli 256
Felix Rodriguez Martin 244
Barnabas Toth 228
Aline Marie Menezes Wanderlei 224
Sveta Marjanovic 212
Dietmar Pree 210
Pio Leonardi 194
Kleszek 172
Steve Muir 131
Jan de Heer 129
Francisco Carlos 127
Luciano Rezende 100
A. Jurcovich, M. Meoli E E. Franzese 91
Kamal Fadlaoui 89
Vinicius Alves 86
Jiang Yong Ming 85
Nino Aspesi 54
Alessandro Jurcovich E Marco Meoli 50
777ch 48
Mathias Liesener 47
Dietmar Pree and Rade Belic 41
Jose Milan Vega 40
Chaoying Dai, Ben Li and Michel Toulouse 39
Rade Belic and Jan de Heer 38
Jaera 38
Fausto Peirano 38
Enzo Franzese E Alessandro Jurcovich 34
Gino Grazin and Rade Belic 31
Andrei Ochmat 31
Stefano de Martino 30
Marco Meoli-alessandro Jurcovich-enzo Franzese 27
Dragan Stojiljkovic 27
Alessandro Jurcovich E Enzo Franzese 26
Marco Meoli E Alessandro Jurcovich 24
Enzo Franzese E Marco Meoli 24
Antonio Franzese 20
Jan de Heer and Rade Belic 19
A. Jurcovich, E. Franzese E M. Meoli 17
Roy Gourgi 14
Weberazevedo 13
Kabila 11
Flavio.perona 11
Weber Azevedo 10
Igor Lazebnik 10
Sildemar Castro 8
Adolf Muehl 8
Riccardo Bertolo 7
Marco Meoli-alessandro Jurcovich 7
Enzo Franzese E Dietmar Pree 7
Daryl Burns 7
Sveta Marjanovic and Anastasios Tampakis 6
Mario Pina 6
Karsten Schölzel 6
Hillary 6
W.h.mills and R.c.mullin 5
Enzo Franzese E Weber Azevedo 5
W.h.mills 4
Sveta Marjanovicandanastasios Tampakis 4
Riccardo Bertolo and Francesco Santisi 4
Rade Belic and Dietmar Pree 4
Leopio 4
Ivan Baptiste and Rade Belic 4
Fctv 4
Fair_play 4
Enzo Franzese E Nino Aspesi 4
Michael Damb 3
Marco Meoli and Alessandro Jurcovich 3
Marco Meoli Alessandro Jurcovich 3
Enzo Franzese E Michael Dambmann 3
Claus Friis 3
Alessandro Jurcovich E Stefano de Martino 3
Weber Azevedo E Enzo Franzese 2
Tarullig / Aspesi 2
Spada Mauro 2
Riccardo Bertolo and Jan de Heer 2
Ricardo Ramalho 2
Paolo Ferlaino 2
Meoli Marco 2
Marco Meoli E Enzo Franzese 2
Marco Meoli E Dietmar Pree 2
Karsten Scholzel 2
Iliya Bluskov 2
Genivaldo Pereira 2
Enzo Franzese E Terenzio Lazzarotto 2
Enzo Franzese E Prize 2
Bluskov and Hamalainen 2
Alessandro Jurcovich-marco Meoli-enzo Franzese 2
Alessandro Jurcovich - Nino Aspesi 2
Adolf Muehl and Dietmar Pree 2
W. H. Mills 1
Tung Le 1
Tarullig/aspesi 1
Tarullig and Kabila 1
Tarullig 1
Steve Muir, Improving One By Jan de Heer 1
Spada Mauro Bellariva 1
Simple Construction: Doubled (50,9,3) and Deleted An Element 1
Simple Construction: Doubled (50,8,3) and Deleted An Element 1
Simple Construction: Doubled (50,8,2) and Deleted An Element 1
Simple Construction: Doubled (50,6,2) and Deleted An Element 1
Simple Construction: Doubled (50,11,3) and Deleted An Element 1
Simple Construction: Doubled (50,11,2) and Deleted An Element 1
Simple Construction: Doubled (50,10,4) and Deleted An Element 1
Simple Construction: Doubled (50,10,3) and Deleted An Element 1
Simple Construction: Doubled (50,10,2) and Deleted An Element 1
Ricardo Sepulveda and Anastasios Tampakis 1
Quadrupling Construction 1
Qlatino 1
Peter Rosendahl 1
Paramini and Kabila and Aspesi 1
Nino Aspesi E Enzo Franzese 1
Nino Aspesi - Moreno Paramini 1
Nino Aspesi - Alessandro Jurcovich 1
Namyk Kemal Erdogan 1
Marjanovic Jurcovich Aspesi 1
Mario Tessuto 1
Marco Meoli Sveta Marjanovic 1
Marco Meoli - Alessandro Jurcovich - Enzo Franzese 1
M. Meoli, A. Jurcovich E E. Franzese 1
Leo Pio 1
Lazzarotto Terenzio 1
Kl 1
Kinsky and Genivaldo Pereira 1
Kair_play 1
K 1
Jose Maria Milan 1
Jan de Heer With Ininuga By Uros Boltin 1
J 1
Grzesiek 1
Gerasorte Online 1
Fernando Villanova 1
Enzo Franzese E Flavio Perona 1
Edi8 1
Dolce Remi 1
Daniel Morais 1
Chaoying Dai, Ben Li and Michel Toulouse, Reduced By Rade Belic 1
Carmine Iorio 1
Bigmax 1
Bellariva 1
Aspesi - Paramini - Tosi 1
Aspesi - Paramini - Marjanovic 1
Anastasios Tampakis and Sveta Marjanovic 1
Altopalato Bellariva 1
Alexandre Spaeth 1
Alessandro Jurcovich-sveta Marjanovic-marco Meoli 1
Alessandro Jurcovich Marco Meoli Enzo Franzese 1
Adolf Muehl and Rade Belic And Dietmar Pree 1
A. Tampakis and A. Jurchovich 1
A. Jurcovich, M. Meoli E E. Franzese E M. Meoli 1
A. Betten, R. Laue and A. Wassermann 1
42066 1

Methods used in current tables

Private tools 3018
Dynamic programming construction 1464
unknown1360
Simple construction 918
Multiple 611
Lex covering 258
Constructed 223
Simulated annealing 133
Dynamic programming covering 132
Wheel generator 81
Simple construction: multiple 70
Simple construction: combined 70
Simple construction: induced 63
Lexicographic greedy covering 57
Jymccdd programming 43
Dynamic programming 40
Dynamic construction 40
Simple construction: deleted element 32
Private tool 28
Tabu search 27
Random greedy covering 23
Cyclic covering found by search program 20
Simple construction: added element to c(v-1,k-1,t) covering 18
Cyclic covering 18
Simple optimization 17
Steiner quadruple system 16
Sidorenko construction 14
Constructed using simulated annealing 11
Simple combine 10
Design is based on c (v - 1, k, t) = b - v 10
Cyclic construction 10
Simulated annealing covering 9
See paper by jrj abel et al. in discrete mathematics 307 (2007) 9
Cyclic covering found by a search program 9
Nurmela and ostergard simulated annealing cover 8
Nurmela-ostergard symmetric covering 7
Affine geometry covering 7
Induced 6
Exhaustive search 6
Covering provided by rade belic 6
Wheel generator, based on jan de heer and steve muir work 5
Steiner triple system 5
Sidorenko method 5
See jct series a 49, 308-322 (1988) 5
Extraction/remainder 5
Simple construction: added element to c(v,k-1,t) covering 4
See journal 4
Nurmela-ostergard simulated annealing covering design 4
Hanani construction (see canadian journal 4
Cyclic symmetry 4
Constructed using difference families 4
Wo - otimizador de rodas 3
Wheel generator and covermaster 3
Using ininuga, by uros boltin 3
Steiner system 3
Reverse engineering smaller systems 3
Projective plane 3
Mills, jcta 13 (1972) pp. 55-78. 3
Mills, ars combinatoria, 8 (1979) pg. 247 3
Mills, ars combinatoria, 8 (1979) pg. 231 3
Mills, ars combinatoria 8 (1979) pp. 199-315 3
Found by a hill-climbing program 3
Cyclic steiner system 3
Covering provided by alex sidorenko (personal communication) 3
Covering found by a hill-climbing program 3
Constructed using dynamic programming 3
Colex greedy covering 3
Steiner system (derived) 2
Simple method construction 2
Several methods (including sa) 2
Nurmela-ostergard simulated annealing covering 2
Modified cover32 routine by dietmar pree 2
Jcd 1998, pp. 21-41 2
Ininuga 2
Hill-climb on cyclic orbits 2
Hill-climb on affine orbits 2
Covering provided by john cock (personal communication) 2
Covering provided by dietmar pree 2
Covering pairs by quads: mills, jcta 15:138-166, 1973. 2
Constructed using difference sets 2
Constructed by simulated annealing 2
Communicated by d. todorov, using pg(2,4) 2
Communicated by d. todorov, using pg(2,3) 2
Affine plane 2
Wheeling systems checker 1
Wheel generator, based on chaoying dai, ben li and michel toulouse work 1
Wheel generator and private tools 1
Using td(6,16) and 6*modified c(18,6,2,2) 1
Using td(6,15) and 6*modified c(18,6,2,2) 1
Using resolvable c(72,4,2), see lamken, mullen and rees (jcd, 1997-1) 1
Using resolvable c(68,4,2), see lamken, mullen and rees (jcd, 1997-1) 1
Using rc(60,3,2) by lamken and mills (1993) 1
Using rc(54,3,2) 1
Using rc(45,3,2) 1
Using dietmar pree version 1
Using a resolvable c(54,6,2,2) 1
Using a 4−gdd 1
Using a (v,4,22*)-pbd and c(22,4,2) 1
Unusual methods 1
Tripling a resolvable c(25,5,2) 1
Td(7,13) and 7 * modified c(15,7,2) 1
Td(4,24) + 4*c(27,4,2) 1
Td(4,24) + 4 * c(26,4,2) 1
Td(4,23) + 4 * c(25,4,2) 1
Td(4,19) & 4 * c(21,4,2) 1
Td(4,18) + 4 * c(21,4,2) 1
Td(4,15) and 4 * modified c(18,4,2) 1
Td(4,12) & 4 * c(15,4,2) 1
Superfluous-element hill climb on a random greedy covering 1
Superfluous-element hill climb on a covering 1
Steiner system, taken 1
Simple multiple 1
Simple construction: doubled (50,8,3) and deleted an element 1
Simple construction: doubled (50,8,2) and deleted an element 1
Simple construction: doubled (50,11,2) and deleted an element 1
Simple construction: doubled (50,10,2) and deleted an element 1
Simple construction: 1
See w h mills in congressus numerantium 10 (1974) pp563-581 1
See paper in journal 1
See j comb des , vol. 15, no. 6, pp. 511-533, 2007 1
See designs, codes and cryptography 17 (1999), 181-186 1
Reverse engineering 1
Replicate 4 columns 1
Quadrupling construction 1
Quadrupling a full c(10,5,5) 1
Produced with covermaster (by john rawson), wheelgenerator (by anastasios tampakis) and private tools. 1
Private tools - assisted by wheel generator 1
Privat tools 1
Of,28,10,6,2899 1
Of,24,15,7,165 1
Normal methods 1
Mills, ars combinatoria, 8 (1979) pg. 270 1
Mills, ars combinatoria, 8 (1979) pg. 254 1
Mill, jcta 15 (1973) 138-166 1
Method 1
Marco meoli 1
Korelacje_777ch__farplay_v1 1
Jymccdd programmingj 1
Ininuga (by uros boltin) 1
Group theory 1
From td(9,9) and 9*c(14,9,2,2,3) with 5 holes 1
From td(7,12) and 7*c(15,7,2,2,6) with 3 holes 1
From td(7,12) and 7*c(13,7,2,2,5) with 2 holes 1
From 57,8,2 1
From 1-flat on 42 numbers 1
Ex 8 1
Ex 62 1
Ex 54 1
Ex 28 1
Ex 1988 1
Ex 16 1
Ex 15 1
Ex 13 1
Doubling resolvable c(25,5,2) 1
Doubling c(42,4,3) 1
Doubling c(36,4,3) 1
Doubling c(30,4,3) 1
Doubling c(18,4,3) 1
Cyclic symmetrical 1
Cyclic covering on z5*z7 1
Cyclic covering on z3*z17 with one point at infinity 1
Cyclic 1
Covering provided by konstantin katskov, found by exhaustive search 1
Covering produced by floyd l. oats, using a ranking and reduction process 1
Covering pairs by quints, mullin, jcmcc 2:133-146, 1987 1
Covering pairs by quints, mills & mullin, jcta 49:308-322, 1988 1
Covering found by rade belic 1
Covering found by john rawson 1
Covering 1
Construction combined 1
Communicated by d. todorov 1
Combinado 1
Chain rule (64,32,6)x(32,24,6) 1
Block-array construction (gordon, patashnik, petro and taylor) 1
Block covering 1
Based on work by kleszek 1
Based on work by chaoying dai, ben li and michel toulouse 1