Mod-5-Cohomology of Co3, a group of order 495766656000

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General information on the group


Structure of the cohomology ring

This cohomology ring is isomorphic to the cohomology ring of a subgroup, namely H*(Normalizer(Co3,Centre(SylowSubgroup(Co3,5))); GF(5)).

General information

About the group Ring generators Ring relations Completion information Restriction maps

Ring generators

The cohomology ring has 12 minimal generators of maximal degree 40:

  1. a_7_0, a nilpotent element of degree 7
  2. b_8_0, an element of degree 8
  3. a_15_1, a nilpotent element of degree 15
  4. a_16_1, a nilpotent element of degree 16
  5. a_18_0, a nilpotent element of degree 18
  6. a_19_0, a nilpotent element of degree 19
  7. a_23_1, a nilpotent element of degree 23
  8. a_24_1, a nilpotent element of degree 24
  9. a_27_1, a nilpotent element of degree 27
  10. b_28_0, an element of degree 28
  11. a_39_1, a nilpotent element of degree 39
  12. c_40_1, a Duflot element of degree 40

About the group Ring generators Ring relations Completion information Restriction maps

Ring relations

There are 6 "obvious" relations:
   a_7_02, a_15_12, a_19_02, a_23_12, a_27_12, a_39_12

Apart from that, there are 52 minimal relations of maximal degree 67:

  1. a_7_0·a_15_1
  2. a_16_1·a_7_0
  3. b_8_0·a_15_1
  4. b_8_0·a_16_1
  5. a_18_0·a_7_0
  6. b_8_0·a_18_0 − 2·a_7_0·a_19_0
  7. a_7_0·a_23_1
  8. a_16_1·a_15_1
  9. a_24_1·a_7_0
  10. b_8_0·a_23_1
  11. a_16_12
  12. b_8_0·a_24_1
  13. a_18_0·a_15_1
  14. a_16_1·a_18_0
  15. a_7_0·a_27_1
  16. a_15_1·a_19_0
  17. a_16_1·a_19_0
  18. b_28_0·a_7_0 + 2·b_8_0·a_27_1
  19. a_18_02
  20. a_18_0·a_19_0
  21. a_15_1·a_23_1
  22. a_16_1·a_23_1
  23. a_24_1·a_15_1
  24. a_16_1·a_24_1
  25. a_18_0·a_23_1
  26. a_18_0·a_24_1
  27. a_15_1·a_27_1
  28. a_19_0·a_23_1
  29. a_16_1·a_27_1
  30. a_24_1·a_19_0
  31. b_28_0·a_15_1
  32. a_16_1·b_28_0
  33. a_18_0·a_27_1
  34. a_19_0·a_27_1 − 2·a_7_0·a_39_1
  35. a_18_0·b_28_0 + 2·a_7_0·a_39_1
  36. a_24_1·a_23_1
  37. b_28_0·a_19_0 + b_8_0·a_39_1
  38. a_24_12
  39. a_23_1·a_27_1
  40. a_24_1·a_27_1
  41. b_28_0·a_23_1
  42. a_24_1·b_28_0
  43. a_15_1·a_39_1
  44. a_16_1·a_39_1
  45. b_28_0·a_27_1 + b_8_0·c_40_1·a_7_0
  46. b_28_02 − 2·b_8_02·c_40_1
  47. a_18_0·a_39_1
  48. a_19_0·a_39_1
  49. a_23_1·a_39_1
  50. a_24_1·a_39_1
  51. a_27_1·a_39_1 − c_40_1·a_7_0·a_19_0
  52. b_28_0·a_39_1 + 2·b_8_0·c_40_1·a_19_0


About the group Ring generators Ring relations Completion information Restriction maps

Data used for Benson′s test


About the group Ring generators Ring relations Completion information Restriction maps

Restriction maps

Expressing the generators as elements of H*(Normalizer(Co3,Centre(SylowSubgroup(Co3,5))); GF(5))

  1. a_7_0a_7_0
  2. b_8_0b_8_0
  3. a_15_1a_15_1
  4. a_16_1a_16_1
  5. a_18_0a_18_0
  6. a_19_0a_19_0
  7. a_23_1a_23_1
  8. a_24_1a_24_1
  9. a_27_1a_27_1
  10. b_28_0b_28_0
  11. a_39_1a_39_1
  12. c_40_1c_40_1

Restriction map to the greatest el. ab. subgp. in the centre of a Sylow subgroup, which is of rank 1

  1. a_7_00, an element of degree 7
  2. b_8_00, an element of degree 8
  3. a_15_10, an element of degree 15
  4. a_16_10, an element of degree 16
  5. a_18_00, an element of degree 18
  6. a_19_00, an element of degree 19
  7. a_23_10, an element of degree 23
  8. a_24_10, an element of degree 24
  9. a_27_10, an element of degree 27
  10. b_28_00, an element of degree 28
  11. a_39_10, an element of degree 39
  12. c_40_1 − 2·c_2_020, an element of degree 40

Restriction map to a maximal el. ab. subgp. of rank 2 in a Sylow subgroup

  1. a_7_02·c_2_23·a_1_1, an element of degree 7
  2. b_8_0 − c_2_24, an element of degree 8
  3. a_15_10, an element of degree 15
  4. a_16_10, an element of degree 16
  5. a_18_0c_2_1·c_2_27·a_1_0·a_1_1 − c_2_15·c_2_23·a_1_0·a_1_1, an element of degree 18
  6. a_19_0 − c_2_1·c_2_28·a_1_0 + c_2_12·c_2_27·a_1_1 + c_2_15·c_2_24·a_1_0
       − c_2_16·c_2_23·a_1_1, an element of degree 19
  7. a_23_10, an element of degree 23
  8. a_24_10, an element of degree 24
  9. a_27_1c_2_12·c_2_211·a_1_1 − 2·c_2_16·c_2_27·a_1_1 + c_2_110·c_2_23·a_1_1, an element of degree 27
  10. b_28_0c_2_12·c_2_212 − 2·c_2_16·c_2_28 + c_2_110·c_2_24, an element of degree 28
  11. a_39_1 − c_2_13·c_2_216·a_1_0 + c_2_14·c_2_215·a_1_1 − 2·c_2_17·c_2_212·a_1_0
       + 2·c_2_18·c_2_211·a_1_1 + 2·c_2_111·c_2_28·a_1_0 − 2·c_2_112·c_2_27·a_1_1
       + c_2_115·c_2_24·a_1_0 − c_2_116·c_2_23·a_1_1, an element of degree 39
  12. c_40_1 − 2·c_2_14·c_2_216 − 2·c_2_18·c_2_212 − 2·c_2_112·c_2_28 − 2·c_2_116·c_2_24
       − 2·c_2_120, an element of degree 40

Restriction map to a maximal el. ab. subgp. of rank 2 in a Sylow subgroup

  1. a_7_02·c_2_23·a_1_1, an element of degree 7
  2. b_8_0 − c_2_24, an element of degree 8
  3. a_15_10, an element of degree 15
  4. a_16_10, an element of degree 16
  5. a_18_0c_2_1·c_2_27·a_1_0·a_1_1 − c_2_15·c_2_23·a_1_0·a_1_1, an element of degree 18
  6. a_19_0 − c_2_1·c_2_28·a_1_0 + c_2_12·c_2_27·a_1_1 + c_2_15·c_2_24·a_1_0
       − c_2_16·c_2_23·a_1_1, an element of degree 19
  7. a_23_10, an element of degree 23
  8. a_24_10, an element of degree 24
  9. a_27_1c_2_12·c_2_211·a_1_1 − 2·c_2_16·c_2_27·a_1_1 + c_2_110·c_2_23·a_1_1, an element of degree 27
  10. b_28_0c_2_12·c_2_212 − 2·c_2_16·c_2_28 + c_2_110·c_2_24, an element of degree 28
  11. a_39_1 − c_2_13·c_2_216·a_1_0 + c_2_14·c_2_215·a_1_1 − 2·c_2_17·c_2_212·a_1_0
       + 2·c_2_18·c_2_211·a_1_1 + 2·c_2_111·c_2_28·a_1_0 − 2·c_2_112·c_2_27·a_1_1
       + c_2_115·c_2_24·a_1_0 − c_2_116·c_2_23·a_1_1, an element of degree 39
  12. c_40_1 − 2·c_2_14·c_2_216 − 2·c_2_18·c_2_212 − 2·c_2_112·c_2_28 − 2·c_2_116·c_2_24
       − 2·c_2_120, an element of degree 40

Restriction map to a maximal el. ab. subgp. of rank 2 in a Sylow subgroup

  1. a_7_02·c_2_23·a_1_1, an element of degree 7
  2. b_8_0 − c_2_24, an element of degree 8
  3. a_15_10, an element of degree 15
  4. a_16_10, an element of degree 16
  5. a_18_0 − c_2_1·c_2_27·a_1_0·a_1_1 + c_2_15·c_2_23·a_1_0·a_1_1, an element of degree 18
  6. a_19_0c_2_1·c_2_28·a_1_0 − c_2_12·c_2_27·a_1_1 − c_2_15·c_2_24·a_1_0
       + c_2_16·c_2_23·a_1_1, an element of degree 19
  7. a_23_10, an element of degree 23
  8. a_24_10, an element of degree 24
  9. a_27_1 − c_2_12·c_2_211·a_1_1 + 2·c_2_16·c_2_27·a_1_1 − c_2_110·c_2_23·a_1_1, an element of degree 27
  10. b_28_0 − c_2_12·c_2_212 + 2·c_2_16·c_2_28 − c_2_110·c_2_24, an element of degree 28
  11. a_39_1 − c_2_13·c_2_216·a_1_0 + c_2_14·c_2_215·a_1_1 − 2·c_2_17·c_2_212·a_1_0
       + 2·c_2_18·c_2_211·a_1_1 + 2·c_2_111·c_2_28·a_1_0 − 2·c_2_112·c_2_27·a_1_1
       + c_2_115·c_2_24·a_1_0 − c_2_116·c_2_23·a_1_1, an element of degree 39
  12. c_40_1 − 2·c_2_14·c_2_216 − 2·c_2_18·c_2_212 − 2·c_2_112·c_2_28 − 2·c_2_116·c_2_24
       − 2·c_2_120, an element of degree 40

Restriction map to a maximal el. ab. subgp. of rank 2 in a Sylow subgroup

  1. a_7_02·c_2_23·a_1_1, an element of degree 7
  2. b_8_0 − c_2_24, an element of degree 8
  3. a_15_10, an element of degree 15
  4. a_16_10, an element of degree 16
  5. a_18_0 − c_2_1·c_2_27·a_1_0·a_1_1 + c_2_15·c_2_23·a_1_0·a_1_1, an element of degree 18
  6. a_19_0c_2_1·c_2_28·a_1_0 − c_2_12·c_2_27·a_1_1 − c_2_15·c_2_24·a_1_0
       + c_2_16·c_2_23·a_1_1, an element of degree 19
  7. a_23_10, an element of degree 23
  8. a_24_10, an element of degree 24
  9. a_27_1 − c_2_12·c_2_211·a_1_1 + 2·c_2_16·c_2_27·a_1_1 − c_2_110·c_2_23·a_1_1, an element of degree 27
  10. b_28_0 − c_2_12·c_2_212 + 2·c_2_16·c_2_28 − c_2_110·c_2_24, an element of degree 28
  11. a_39_1 − c_2_13·c_2_216·a_1_0 + c_2_14·c_2_215·a_1_1 − 2·c_2_17·c_2_212·a_1_0
       + 2·c_2_18·c_2_211·a_1_1 + 2·c_2_111·c_2_28·a_1_0 − 2·c_2_112·c_2_27·a_1_1
       + c_2_115·c_2_24·a_1_0 − c_2_116·c_2_23·a_1_1, an element of degree 39
  12. c_40_1 − 2·c_2_14·c_2_216 − 2·c_2_18·c_2_212 − 2·c_2_112·c_2_28 − 2·c_2_116·c_2_24
       − 2·c_2_120, an element of degree 40

Restriction map to a maximal el. ab. subgp. of rank 2 in a Sylow subgroup

  1. a_7_02·c_2_23·a_1_1, an element of degree 7
  2. b_8_0 − c_2_24, an element of degree 8
  3. a_15_10, an element of degree 15
  4. a_16_10, an element of degree 16
  5. a_18_0c_2_1·c_2_27·a_1_0·a_1_1 − c_2_15·c_2_23·a_1_0·a_1_1, an element of degree 18
  6. a_19_0 − c_2_1·c_2_28·a_1_0 + c_2_12·c_2_27·a_1_1 + c_2_15·c_2_24·a_1_0
       − c_2_16·c_2_23·a_1_1, an element of degree 19
  7. a_23_10, an element of degree 23
  8. a_24_10, an element of degree 24
  9. a_27_1c_2_12·c_2_211·a_1_1 − 2·c_2_16·c_2_27·a_1_1 + c_2_110·c_2_23·a_1_1, an element of degree 27
  10. b_28_0c_2_12·c_2_212 − 2·c_2_16·c_2_28 + c_2_110·c_2_24, an element of degree 28
  11. a_39_1 − c_2_13·c_2_216·a_1_0 + c_2_14·c_2_215·a_1_1 − 2·c_2_17·c_2_212·a_1_0
       + 2·c_2_18·c_2_211·a_1_1 + 2·c_2_111·c_2_28·a_1_0 − 2·c_2_112·c_2_27·a_1_1
       + c_2_115·c_2_24·a_1_0 − c_2_116·c_2_23·a_1_1, an element of degree 39
  12. c_40_1 − 2·c_2_14·c_2_216 − 2·c_2_18·c_2_212 − 2·c_2_112·c_2_28 − 2·c_2_116·c_2_24
       − 2·c_2_120, an element of degree 40

Restriction map to a maximal el. ab. subgp. of rank 2 in a Sylow subgroup

  1. a_7_02·c_2_23·a_1_1, an element of degree 7
  2. b_8_0 − c_2_24, an element of degree 8
  3. a_15_10, an element of degree 15
  4. a_16_10, an element of degree 16
  5. a_18_0 − c_2_1·c_2_27·a_1_0·a_1_1 + c_2_15·c_2_23·a_1_0·a_1_1, an element of degree 18
  6. a_19_0c_2_1·c_2_28·a_1_0 − c_2_12·c_2_27·a_1_1 − c_2_15·c_2_24·a_1_0
       + c_2_16·c_2_23·a_1_1, an element of degree 19
  7. a_23_10, an element of degree 23
  8. a_24_10, an element of degree 24
  9. a_27_1 − c_2_12·c_2_211·a_1_1 + 2·c_2_16·c_2_27·a_1_1 − c_2_110·c_2_23·a_1_1, an element of degree 27
  10. b_28_0 − c_2_12·c_2_212 + 2·c_2_16·c_2_28 − c_2_110·c_2_24, an element of degree 28
  11. a_39_1 − c_2_13·c_2_216·a_1_0 + c_2_14·c_2_215·a_1_1 − 2·c_2_17·c_2_212·a_1_0
       + 2·c_2_18·c_2_211·a_1_1 + 2·c_2_111·c_2_28·a_1_0 − 2·c_2_112·c_2_27·a_1_1
       + c_2_115·c_2_24·a_1_0 − c_2_116·c_2_23·a_1_1, an element of degree 39
  12. c_40_1 − 2·c_2_14·c_2_216 − 2·c_2_18·c_2_212 − 2·c_2_112·c_2_28 − 2·c_2_116·c_2_24
       − 2·c_2_120, an element of degree 40


About the group Ring generators Ring relations Completion information Restriction maps




Created with the Sage cohomology package written by Simon King and David Green



Last change: 11.09.2015