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Diffstat (limited to 'README.md')
| -rw-r--r-- | README.md | 60 |
1 files changed, 54 insertions, 6 deletions
| @@ -61,18 +61,66 @@ sage: KummerDegree([144,27,49/81,-1/125,121/13],36*10^6,36*10^6) | |||
| 61 | 61 | ||
| 62 | ## TotalKummerFailure( G ) | 62 | ## TotalKummerFailure( G ) |
| 63 | 63 | ||
| 64 | Outputs the description of the failure of maximality for all possible values of M and N. Here G is given as a list of generators (not necessarily a basis). G can also contain torsion. If G = <-1>, the program stops immediately. | 64 | Outputs the description of the failure of maximality for all possible values |
| 65 | of M and N. | ||
| 65 | 66 | ||
| 66 | Example: | 67 | INPUT: |
| 68 | G - a list of generators for the group G | ||
| 69 | |||
| 70 | OUPUT: | ||
| 71 | The first part of the output consist of two positive integers M_0 and N_0. | ||
| 72 | N_0 is always a divisor of M_0. | ||
| 73 | |||
| 74 | The second part of the output can be either one or two tables, depending on | ||
| 75 | the group G. In case -1 is not an element of G, there is only one table, | ||
| 76 | otherwise two. | ||
| 77 | |||
| 78 | In case -1 does not belong to G: | ||
| 79 | The rows of the table(s) are labelled with divisors of N_0, while the columns | ||
| 80 | with divisors of M_0. The total failure of maximality of the Kummer Extension | ||
| 81 | Q_{M,N}, i.e. the ratio between phi(M)*N^rank(G) and the degree of Q_{M,N} | ||
| 82 | over Q, is given by the (i,j)-th entry of the table for i=gcd(N,N_0) and | ||
| 83 | j=gcd(M,M_0). | ||
| 84 | |||
| 85 | In case -1 belongs to G, we need to distinguish two cases, depending on the | ||
| 86 | parity of M/N. The two tables are similar to the case described | ||
| 87 | above, and can be seen in the example below. | ||
| 88 | |||
| 89 | The output includes an explanation of the tables and how to read them to | ||
| 90 | deduce the actual degrees (that can be computed with KummerDegree). | ||
| 91 | |||
| 92 | EXAMPLES: | ||
| 67 | 93 | ||
| 68 | ``` | 94 | ``` |
| 95 | sage: TotalKummerFailure([-36,12]) | ||
| 96 | M_0 = 24 | ||
| 97 | N_0 = 8 | ||
| 69 | 98 | ||
| 99 | The following table shows the total failure of Kummer degrees. | ||
| 100 | The degree of the Kummer extension (M,N) is e / f, where e = phi(M)*N^rank(G) | ||
| 101 | and f is the entry of the table below at the row labelled with gcd(N,N0) and | ||
| 102 | the column labelled with gcd(M,M0). | ||
| 103 | |||
| 104 | | 1 2 3 4 6 8 12 24 | ||
| 105 | - - - - - - - - - - | ||
| 106 | 1 | 1 1 1 1 1 1 1 1 | ||
| 107 | 2 | 1 1 1 2 2 2 4 4 | ||
| 108 | 4 | 4 4 4 4 4 4 8 8 | ||
| 109 | 8 | 4 4 4 4 4 4 4 8 | ||
| 110 | |||
| 111 | ``` | ||
| 112 | |||
| 113 | ``` | ||
| 70 | sage: TotalKummerFailure([-36,12,-1]) | 114 | sage: TotalKummerFailure([-36,12,-1]) |
| 71 | M_0 = 24 | 115 | M_0 = 24 |
| 72 | N_0 = 8 | 116 | N_0 = 8 |
| 73 | 117 | ||
| 74 | The following table shows the total failure of Kummer degrees in case the quotient M/N is EVEN. | 118 | The following table shows the total failure of Kummer degrees in case the |
| 75 | The degree of the Kummer extension (M,N) is e / f, where e = phi(M)*N^rank(G) if N is odd and e = 2*phi(M)*N^rank(G) if N is even and f is the entry of the table below at the row labelled with gcd(N,N0) and the column labelled with gcd(M,M0). | 119 | quotient M/N is EVEN. |
| 120 | The degree of the Kummer extension (M,N) is e / f, where e = phi(M)*N^rank(G) | ||
| 121 | if N is odd and e = 2*phi(M)*N^rank(G) if N is even and f is the entry of the | ||
| 122 | table below at the row labelled with gcd(N,N0) and the column labelled with | ||
| 123 | gcd(M,M0). | ||
| 76 | 124 | ||
| 77 | | 1 2 3 4 6 8 12 24 | 125 | | 1 2 3 4 6 8 12 24 |
| 78 | - - - - - - - - - - | 126 | - - - - - - - - - - |
| @@ -81,7 +129,8 @@ The degree of the Kummer extension (M,N) is e / f, where e = phi(M)*N^rank(G) if | |||
| 81 | 4 | 4 4 4 4 4 8 8 16 | 129 | 4 | 4 4 4 4 4 8 8 16 |
| 82 | 8 | 8 8 8 8 8 8 8 16 | 130 | 8 | 8 8 8 8 8 8 8 16 |
| 83 | 131 | ||
| 84 | The following table shows the total failure of Kummer degrees if the quotient M/N is ODD and is read as the previous one. | 132 | The following table shows the total failure of Kummer degrees if the quotient |
| 133 | M/N is ODD and is read as the previous one. | ||
| 85 | 134 | ||
| 86 | | 1 2 3 4 6 8 12 24 | 135 | | 1 2 3 4 6 8 12 24 |
| 87 | - - - - - - - - - - | 136 | - - - - - - - - - - |
| @@ -92,4 +141,3 @@ The following table shows the total failure of Kummer degrees if the quotient M/ | |||
| 92 | 141 | ||
| 93 | ``` | 142 | ``` |
| 94 | 143 | ||
| 95 | |||
