The tables currently have 9142 entries from 73 different contributors


last updated at 2017-04-21 13:02:25

Top Contributors

LJCR 4428
Jan de Heer and Steve Muir 2875
Colin Barker 321
Michael Dambmann 248
Terenzio Lazzarotto 151
Tommaso Tanto 145
Pio Leonardi 98
Flavio Perona 90
Anastasios Tampakis 86
Enzo Franzese 81
Kamal Fadlaoui 74
Jan de Heer 47
Alessandro Jurcovich 38
Rade Belic and Dragan Stojiljkovic 35
Mathias Liesener 34
Rade Belic 32
Barnabas Toth 28
Gerald Unger 27
Kinski and Genivaldo Pereira 26
Dietmar Pree 23
Andrei Ochmat 23
Vinicius Alves 22
Marco Meoli 22
Chaoying Dai, Ben Li and Michel Toulouse 22
Felix Rodriguez Martin 20
Luciano Rezende 18
Rade Belic and Jan de Heer 13
Adolf Muehl 13
Sveta Marjanovic 9
Aline Marie Menezes Wanderlei 9
Karsten Schölzel 6
W.h.mills and R.c.mullin 5
Roy Gourgi 5
Kleszek 5
W.h.mills 4
Sveta Marjanovic and Anastasios Tampakis 4
Jan de Heer and Rade Belic 4
Daryl Burns 4
Alessandro Jurcovich E Marco Meoli 3
Sveta Marjanovicandanastasios Tampakis 2
Steve Muir 2
Mario Pina 2
Marco Meoli E Alessandro Jurcovich 2
Iliya Bluskov 2
Guenther Schlegl 2
Francisco Carlos 2
Fausto Peirano 2
Claus Friis 2
Bluskov and Hamalainen 2
Weberazevedo 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
Nino Aspesi - Alessandro Jurcovich 1
Namyk Kemal Erdogan 1
Marco Meoli E Enzo Franzese 1
Kinsky and Genivaldo Pereira 1
Karsten Scholzel 1
Jose Milan Vega 1
Jaera 1
Igor Lazebnik 1
Enzo Franzese E Marco Meoli 1
Dietmar Pree and Rade Belic 1
Dietmar Pree and Adolf Muehl 1
Daniel Morais 1
Chaoying Dai, Ben Li and Michel Toulouse, Reduced By Rade Belic 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 65762 entries from 127 different contributors

All-time Contributors






LJCR 45926
Jan de Heer and Steve Muir 5017
Michael Dambmann 2239
Tommaso Tanto 1733
JCD Article 1632
Flavio Perona 1498
Rade Belic 1441
Terenzio Lazzarotto 1405
Rade Belic and Dragan Stojiljkovic 539
Colin Barker 457
Gerald Unger 343
Enzo Franzese 287
Kinski and Genivaldo Pereira 278
Anastasios Tampakis 257
Felix Rodriguez Martin 244
Barnabas Toth 228
Pio Leonardi 194
Aline Marie Menezes Wanderlei 170
Dietmar Pree 155
Alessandro Jurcovich 149
Steve Muir 131
Marco Meoli 129
Jan de Heer 129
Francisco Carlos 127
Luciano Rezende 100
Kamal Fadlaoui 89
Vinicius Alves 86
Sveta Marjanovic 71
Nino Aspesi 49
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
Gino Grazin and Rade Belic 31
Andrei Ochmat 31
Dragan Stojiljkovic 27
Jan de Heer and Rade Belic 19
Kleszek 16
Stefano de Martino 14
Roy Gourgi 14
Alessandro Jurcovich E Marco Meoli 14
Kabila 11
Flavio.perona 11
Igor Lazebnik 10
Weberazevedo 8
Sildemar Castro 8
Adolf Muehl 8
Weber Azevedo 7
Riccardo Bertolo 7
Daryl Burns 7
Mario Pina 6
Karsten Schölzel 6
W.h.mills and R.c.mullin 5
Sveta Marjanovic and Anastasios Tampakis 5
Marco Meoli E Alessandro Jurcovich 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
Enzo Franzese E Marco Meoli 4
Michael Damb 3
Claus Friis 3
Alessandro Jurcovich E Enzo Franzese 3
Tarullig / Aspesi 2
Riccardo Bertolo and Jan de Heer 2
Ricardo Ramalho 2
Paolo Ferlaino 2
Meoli Marco 2
Marco Meoli E Enzo Franzese 2
Karsten Scholzel 2
Iliya Bluskov 2
Genivaldo Pereira 2
Bluskov and Hamalainen 2
Alessandro Jurcovich E Stefano de Martino 2
Adolf Muehl and Dietmar Pree 2
W. H. Mills 1
Tung Le 1
Tarullig/aspesi 1
Steve Muir, Improving One By Jan de Heer 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
Quadrupling Construction 1
Qlatino 1
Peter Rosendahl 1
Paramini and Kabila and Aspesi 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 1
Leo Pio 1
Lazzarotto Terenzio 1
Kinsky and Genivaldo Pereira 1
Jose Maria Milan 1
Jiang Yong Ming 1
Jan de Heer With Ininuga By Uros Boltin 1
Grzesiek 1
Gerasorte Online 1
Fernando Villanova 1
Enzo Franzese E Alessandro Jurcovich 1
Edi8 1
Daniel Morais 1
Chaoying Dai, Ben Li and Michel Toulouse, Reduced By Rade Belic 1
Aspesi - Paramini - Tosi 1
Aspesi - Paramini - Marjanovic 1
Altopalato Bellariva 1
Alexandre Spaeth 1
Alessandro Jurcovich-sveta Marjanovic-marco Meoli 1
Alessandro Jurcovich - Nino Aspesi 1
Adolf Muehl and Rade Belic And Dietmar Pree 1
A. Tampakis and A. Jurchovich 1
A. Betten, R. Laue and A. Wassermann 1
42066 1

Methods used in current tables

Private tools 2580
Dynamic programming construction 1947
unknown1282
Simple construction 952
Multiple 629
Lex covering 258
Constructed 223
Simulated annealing 191
Dynamic programming covering 135
Simple construction: combined 79
Simple construction: multiple 70
Simple construction: induced 66
Lexicographic greedy covering 57
Wheel generator 49
Dynamic construction 40
Dynamic programming 37
Simple construction: deleted element 31
Tabu search 28
Private tool 28
Random greedy covering 23
Cyclic covering 23
Cyclic covering found by search program 20
Simple construction: added element to c(v-1,k-1,t) covering 18
Steiner quadruple system 16
Simple optimization 16
Sidorenko construction 15
Simple combine 11
Constructed using simulated annealing 11
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
Steiner triple system 5
Sidorenko method 5
See jct series a 49, 308-322 (1988) 5
Extraction/remainder 5
Colex greedy covering 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
Wheel generator, based on jan de heer and steve muir work 3
Using ininuga, by uros boltin 3
Steiner system 3
Reverse engineering smaller systems 3
Projective plane 3
Modified cover32 routine by dietmar pree 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
Steiner system (derived) 2
Simple method construction 2
Several methods (including sa) 2
Nurmela-ostergard simulated annealing covering 2
Jcd 1998, pp. 21-41 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
Using wheel generator 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 (50,10,4) 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
Pritave tools 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
Ininuga (by uros boltin) 1
Induced annealing 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
Extraction 1
Ex 948 1
Ex 831 1
Ex 8 1
Ex 62 1
Ex 54 1
Ex 28 1
Ex 1988 1
Ex 1821 1
Ex 16 1
Ex 15 1
Ex 1491 1
Ex 13 1
Ex 1257 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 chaoying dai, ben li and michel toulouse 1
Based on an improvement by dietmar pree 1