The tables currently have 9137 entries from 83 different contributors


last updated at 2021-04-14 16:14:43

Top Contributors

LJCR 2960
Jan de Heer and Steve Muir 2430
A. West 1230
Dietmar Pree 440
Colin Barker 317
Michael Dambmann 177
Marco Meoli 170
Stefano de Martino 156
Terenzio Lazzarotto 148
Alessandro Jurcovich 133
Anastasios Tampakis 100
Kleszek 80
Kamal Fadlaoui 73
Flavio Perona 60
Enzo Franzese 58
Evandro De Simone 54
Jan de Heer 43
Sveta Marjanovic 41
Mathias Liesener 34
Fair_play 33
777ch 32
Rade Belic 29
Giovanni Acerbi 29
Barnabas Toth 25
Kinski and Genivaldo Pereira 25
Andrei Ochmat 23
Chaoying Dai, Ben Li and Michel Toulouse 21
Felix Rodriguez Martin 18
Luciano Rezende 18
Aline Marie Menezes Wanderlei 18
Adolf Muehl 17
Jiang Yong Ming 17
Vinicius Alves 13
Rade Belic and Jan de Heer 12
Jiang Yong Ming and Jiang Kun Xi 12
Alessandro Jurcovich E Marco Meoli 7
Karsten Schlzel 6
W.h.mills and R.c.mullin 5
Roy Gourgi 5
Weber Azevedo 5
W.h.mills 4
Jan de Heer and Rade Belic 4
Marco Meoli E Alessandro Jurcovich 3
E. Franzese, A. Jurcovich E M. Meoli 3
Iliya Bluskov 2
Rade Belic and Dragan Stojiljkovic 2
Claus Friis 2
Bluskov and Hamalainen 2
Guenther Schlegl 2
Sveta Marjanovicandanastasios Tampakis 2
Daryl Burns 2
Steve Muir 2
Mario Pina 2
Covboy 2
Namyk Kemal Erdogan 1
W. H. Mills 1
Karsten Scholzel 1
Adolf Muehl and Dietmar Pree 1
Igor Lazebnik 1
Tung Le 1
Riccardo Bertolo and Francesco Santisi 1
A. Tampakis and A. Jurchovich 1
Jaera 1
Kinsky and Genivaldo Pereira 1
Jose Milan Vega 1
Dietmar Pree and Adolf Muehl 1
Rade Belic and Dietmar Pree 1
A. Betten, R. Laue and A. Wassermann 1
Riccardo Bertolo and Jan de Heer 1
Dietmar Pree and Rade Belic 1
Alexandre Spaeth 1
Chaoying Dai, Ben Li and Michel Toulouse, Reduced By Rade Belic 1
Marco Meoli-alessandro Jurcovich-enzo Franzese 1
Bigmax 1
A. Jurcovich, M. Meoli E E. Franzese 1
Carmine Iorio 1
Marco Meoli-alessandro Jurcovich 1
Alessandro Jurcovich E Claudio Tosi 1
Tarullig 1
Giovanni Acerbi and Alessandro Jurcovich 1
Alessandro Jurcovich E Giovanni Acerbi 1
Anastasios Tampakis and Sveta Marjanovic 1
Arrastre 1





Overall there have been 82511 entries from 185 different contributors

All-time Contributors






LJCR 51749
Jan de Heer and Steve Muir 6136
Enzo Franzese 2692
Michael Dambmann 2254
Terenzio Lazzarotto 1886
Tommaso Tanto 1799
A. West 1763
JCD Article 1632
Flavio Perona 1533
Rade Belic 1441
Dietmar Pree 1201
Marco Meoli 644
Rade Belic and Dragan Stojiljkovic 539
Jiang Yong Ming and Jiang Kun Xi 505
Alessandro Jurcovich 499
Kleszek 495
Colin Barker 457
Gerald Unger 343
Anastasios Tampakis 340
Stefano de Martino 331
E. Franzese, A. Jurcovich E M. Meoli 326
Kinski and Genivaldo Pereira 278
Aline Marie Menezes Wanderlei 261
Sveta Marjanovic 253
Felix Rodriguez Martin 244
Barnabas Toth 228
Fair_play 225
Pio Leonardi 194
Evandro De Simone 185
777ch 144
Steve Muir 131
Jan de Heer 129
Francisco Carlos 127
Luciano Rezende 100
Giovanni Acerbi 94
Vinicius Alves 91
A. Jurcovich, M. Meoli E E. Franzese 91
Kamal Fadlaoui 89
Jiang Yong Ming 85
Alessandro Jurcovich E Marco Meoli 55
Nino Aspesi 54
Mathias Liesener 47
Dietmar Pree and Rade Belic 41
Jose Milan Vega 40
Chaoying Dai, Ben Li and Michel Toulouse 39
Jaera 38
Rade Belic and Jan de Heer 38
Enzo Franzese E Alessandro Jurcovich 34
Andrei Ochmat 31
Gino Grazin and Rade Belic 31
Weber Azevedo 30
Marco Meoli-alessandro Jurcovich-enzo Franzese 28
Dragan Stojiljkovic 27
Marco Meoli E Alessandro Jurcovich 27
Alessandro Jurcovich E Enzo Franzese 26
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
Adolf Muehl 13
Weberazevedo 13
Flavio.perona 11
Kabila 11
Tarullig 11
Igor Lazebnik 10
Sildemar Castro 8
Marco Meoli-alessandro Jurcovich 8
Riccardo Bertolo 7
Daryl Burns 7
Enzo Franzese E Dietmar Pree 7
Mario Pina 6
Karsten Schlzel 6
Sveta Marjanovic and Anastasios Tampakis 6
Hillary 6
W.h.mills and R.c.mullin 5
Enzo Franzese E Weber Azevedo 5
Anastasios Tampakis and Sveta Marjanovic 5
Riccardo Bertolo and Francesco Santisi 4
Ivan Baptiste and Rade Belic 4
Rade Belic and Dietmar Pree 4
Leopio 4
W.h.mills 4
Sveta Marjanovicandanastasios Tampakis 4
Enzo Franzese E Nino Aspesi 4
Fctv 4
Claus Friis 3
Michael Damb 3
Marco Meoli Alessandro Jurcovich 3
Alessandro Jurcovich E Stefano de Martino 3
Marco Meoli and Alessandro Jurcovich 3
Enzo Franzese E Michael Dambmann 3
K 3
Claudio Tosi 3
Giovanni Acerbi and Terenzio Lazzarotto 3
Alessandro Jurcovich E Free 3
Riccardo Bertolo and Jan de Heer 2
Genivaldo Pereira 2
Ricardo Ramalho 2
Iliya Bluskov 2
Paolo Ferlaino 2
Bluskov and Hamalainen 2
Adolf Muehl and Dietmar Pree 2
Karsten Scholzel 2
Meoli Marco 2
Tarullig / Aspesi 2
Alessandro Jurcovich - Nino Aspesi 2
Marco Meoli E Enzo Franzese 2
Marco Meoli E Dietmar Pree 2
Weber Azevedo E Enzo Franzese 2
Enzo Franzese E Terenzio Lazzarotto 2
Enzo Franzese E Prize 2
Alessandro Jurcovich-marco Meoli-enzo Franzese 2
Spada Mauro 2
Alessandro Jurcovich E Claudio Tosi 2
Alessandro Jurcovich E Giovanni Acerbi 2
Covboy 2
A. Betten, R. Laue and A. Wassermann 1
Namyk Kemal Erdogan 1
Alexandre Spaeth 1
Fernando Villanova 1
Steve Muir, Improving One By Jan de Heer 1
Chaoying Dai, Ben Li and Michel Toulouse, Reduced By Rade Belic 1
Jose Maria Milan 1
Grzesiek 1
Jan de Heer With Ininuga By Uros Boltin 1
Peter Rosendahl 1
Daniel Morais 1
Adolf Muehl and Rade Belic And Dietmar Pree 1
Lazzarotto Terenzio 1
Kinsky and Genivaldo Pereira 1
Gerasorte Online 1
W. H. Mills 1
Leo Pio 1
Qlatino 1
Simple Construction: Doubled (50,6,2) and Deleted An Element 1
Simple Construction: Doubled (50,8,2) and Deleted An Element 1
Simple Construction: Doubled (50,10,2) and Deleted An Element 1
Simple Construction: Doubled (50,11,2) and Deleted An Element 1
Simple Construction: Doubled (50,8,3) and Deleted An Element 1
Simple Construction: Doubled (50,9,3) and Deleted An Element 1
Simple Construction: Doubled (50,10,3) and Deleted An Element 1
Simple Construction: Doubled (50,11,3) and Deleted An Element 1
Simple Construction: Doubled (50,10,4) and Deleted An Element 1
42066 1
Quadrupling Construction 1
Altopalato Bellariva 1
Aspesi - Paramini - Tosi 1
Aspesi - Paramini - Marjanovic 1
Nino Aspesi - Moreno Paramini 1
Paramini and Kabila and Aspesi 1
Tung Le 1
Marjanovic Jurcovich Aspesi 1
Marco Meoli Sveta Marjanovic 1
A. Tampakis and A. Jurchovich 1
Nino Aspesi - Alessandro Jurcovich 1
Edi8 1
Tarullig/aspesi 1
Mario Tessuto 1
Alessandro Jurcovich-sveta Marjanovic-marco Meoli 1
J 1
Nino Aspesi E Enzo Franzese 1
Spada Mauro Bellariva 1
Marco Meoli - Alessandro Jurcovich - Enzo Franzese 1
A. Jurcovich, M. Meoli E E. Franzese E M. Meoli 1
Ricardo Sepulveda and Anastasios Tampakis 1
Bigmax 1
Kl 1
M. Meoli, A. Jurcovich E E. Franzese 1
Alessandro Jurcovich Marco Meoli Enzo Franzese 1
Enzo Franzese E Flavio Perona 1
Carmine Iorio 1
Dolce Remi 1
Bellariva 1
Tarullig and Kabila 1
Kair_play 1
Play_fair 1
A. Jurcovich, G. Acerbi E M. Meoli 1
Giovanni Acerbi and Alessandro Jurcovich 1
Marco Marco 1
Aline Marie Menezes Wanderlei and Evandro De Simone 1
Don Backi 1
Paramini Moreno 1
Arrastre 1
Weber Azevedoandaline Marie 1

Methods used in current tables

Private tools 2297
Local search 1554
unknown1039
Simple construction 871
Dynamic programming construction 612
Multiple 609
Lex covering 258
Constructed 227
Private tool 182
Dynamic programming covering 132
Simulated annealing 119
Wheeling systems checker 4 83
Simple construction: combined 73
Wheel generator 72
Simple construction: multiple 70
Wsc v4 66
Simple construction: induced 63
Lexicographic greedy covering 57
Dynamic construction 43
Korelacje_777ch__fairplay_v4 42
Local search - bluskov pdo technique 41
Dynamic programming 38
Simple construction: deleted element 31
Jymccdd programming 29
Tabu search 27
Random greedy covering 23
Cyclic covering found by search program 20
Sidorenko construction 19
Cyclic covering 18
Simple construction: added element to c(v-1,k-1,t) covering 18
Steiner quadruple system 16
Simple optimization 16
Constructed using simulated annealing 11
Cyclic construction 10
Simple combine 10
Design is based on c (v - 1, k, t) = b - v 10
Cyclic covering found by a search program 9
See paper by jrj abel et al. in discrete mathematics 307 (2007) 9
Simulated annealing covering 9
Wo - otimizador de rodas 9
Group orbit covering design 9
Nurmela and ostergard simulated annealing cover 8
Affine geometry covering 7
Nurmela-ostergard symmetric covering 7
Induced 6
Exhaustive search 6
Covering provided by rade belic 6
Shortened covering 6
Steiner triple system 5
See jct series a 49, 308-322 (1988) 5
Extraction/remainder 5
Sidorenko method 5
Extended covering 5
See journal 4
Constructed using difference families 4
Simple construction: added element to c(v,k-1,t) covering 4
Cyclic symmetry 4
Hanani construction (see canadian journal 4
Nurmela-ostergard simulated annealing covering design 4
Wheeling systems checker 4
Private tools, covermaster and wheelgenerator 4
Colex greedy covering 3
Mills, jcta 13 (1972) pp. 55-78. 3
Found by a hill-climbing program 3
Steiner system 3
Covering found by a hill-climbing program 3
Cyclic steiner system 3
Projective plane 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
Reverse engineering smaller systems 3
Covering provided by alex sidorenko (personal communication) 3
Using ininuga, by uros boltin 3
Using wsc4 3
Korelacje_777ch v5 3
Covering pairs by quads: mills, jcta 15:138-166, 1973. 2
Constructed using difference sets 2
Constructed by simulated annealing 2
Constructed using dynamic programming 2
Communicated by d. todorov, using pg(2,3) 2
Communicated by d. todorov, using pg(2,4) 2
Affine plane 2
Steiner system (derived) 2
Wheel generator, based on jan de heer and steve muir work 2
Covering provided by john cock (personal communication) 2
Several methods (including sa) 2
Jcd 1998, pp. 21-41 2
Nurmela-ostergard simulated annealing covering 2
Hill-climb on affine orbits 2
Covering provided by dietmar pree 2
Hill-climb on cyclic orbits 2
Simple method construction 2
Ininuga 2
Using wheel generator 2
Metaheuristic 2
From 1-flat on 42 numbers 1
Mill, jcta 15 (1973) 138-166 1
See paper in journal 1
Cyclic 1
Td(4,12) & 4 * c(15,4,2) 1
Td(4,15) and 4 * modified c(18,4,2) 1
Using rc(45,3,2) 1
Using a (v,4,22*)-pbd and c(22,4,2) 1
Td(4,18) + 4 * c(21,4,2) 1
Td(4,19) & 4 * c(21,4,2) 1
Using rc(54,3,2) 1
Using rc(60,3,2) by lamken and mills (1993) 1
Td(4,23) + 4 * c(25,4,2) 1
Td(4,24) + 4 * c(26,4,2) 1
Td(4,24) + 4*c(27,4,2) 1
Covering pairs by quints, mills & mullin, jcta 49:308-322, 1988 1
Covering pairs by quints, mullin, jcmcc 2:133-146, 1987 1
Cyclic covering on z5*z7 1
Cyclic covering on z3*z17 with one point at infinity 1
Using a 4−gdd 1
Using resolvable c(68,4,2), see lamken, mullen and rees (jcd, 1997-1) 1
Using resolvable c(72,4,2), see lamken, mullen and rees (jcd, 1997-1) 1
Covering found by john rawson 1
Produced with covermaster (by john rawson), wheelgenerator (by anastasios tampakis) and private tools. 1
See j comb des , vol. 15, no. 6, pp. 511-533, 2007 1
Using td(6,15) and 6*modified c(18,6,2,2) 1
Using td(6,16) and 6*modified c(18,6,2,2) 1
Communicated by d. todorov 1
Using a resolvable c(54,6,2,2) 1
From td(7,12) and 7*c(13,7,2,2,5) with 2 holes 1
From td(7,12) and 7*c(15,7,2,2,6) with 3 holes 1
Td(7,13) and 7 * modified c(15,7,2) 1
From 57,8,2 1
From td(9,9) and 9*c(14,9,2,2,3) with 5 holes 1
Mills, ars combinatoria, 8 (1979) pg. 254 1
Mills, ars combinatoria, 8 (1979) pg. 270 1
Doubling resolvable c(25,5,2) 1
Tripling a resolvable c(25,5,2) 1
Steiner system, taken 1
Doubling c(18,4,3) 1
Reverse engineering 1
Simple construction: 1
Doubling c(30,4,3) 1
See w h mills in congressus numerantium 10 (1974) pp563-581 1
Doubling c(36,4,3) 1
Doubling c(42,4,3) 1
Covering produced by floyd l. oats, using a ranking and reduction process 1
Group theory 1
Covering 1
Privat tools 1
Quadrupling construction 1
Covering provided by konstantin katskov, found by exhaustive search 1
Private tools - assisted by wheel generator 1
Cyclic symmetrical 1
Combinado 1
Ex 8 1
Covering found by rade belic 1
Marco meoli 1
Superfluous-element hill climb on a covering 1
Ininuga (by uros boltin) 1
Ex 16 1
Ex 13 1
Ex 15 1
See designs, codes and cryptography 17 (1999), 181-186 1
Method 1
Based on work by chaoying dai, ben li and michel toulouse 1
Block-array construction (gordon, patashnik, petro and taylor) 1
Ex 28 1
Ex 1988 1
Superfluous-element hill climb on a random greedy covering 1
Block covering 1
Ex 54 1
Ex 62 1
Chain rule (64,32,6)x(32,24,6) 1
Normal methods 1
Quadrupling a full c(10,5,5) 1
Replicate 4 columns 1
Unusual methods 1
Construction combined 1
Of,24,15,7,165 1
Of,28,10,6,2899 1
Wheel generator, based on chaoying dai, ben li and michel toulouse work 1
Based on work by kleszek 1
Wheel generator and covermaster 1
Korelacje_777ch__farplay_v1 1
Korelacje_777ch__fairplay_v2 1
Wsc program 1
Wheeling systems checker 4 - coming soon 1
Simple construction: doubled (50,8,2) and deleted an element 1
Simple construction: doubled (50,10,2) and deleted an element 1
Simple construction: doubled (50,11,2) and deleted an element 1
Simple construction: doubled (50,8,3) and deleted an element 1
Ferramentas particulares 1
Wheel generator and private tools 1
Not wsc v4 1
Wheel generator, covermaster and wo - otimizador de rodas 1
Based on work by a. tampakis 1
Wheeling systems checker, wheel generator and ininuga 1