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@@ -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
64Outputs 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. 64Outputs the description of the failure of maximality for all possible values
65of M and N.
65 66
66Example: 67INPUT:
68G - a list of generators for the group G
69
70OUPUT:
71The first part of the output consist of two positive integers M_0 and N_0.
72N_0 is always a divisor of M_0.
73
74The second part of the output can be either one or two tables, depending on
75the group G. In case -1 is not an element of G, there is only one table,
76otherwise two.
77
78In case -1 does not belong to G:
79The rows of the table(s) are labelled with divisors of N_0, while the columns
80with divisors of M_0. The total failure of maximality of the Kummer Extension
81Q_{M,N}, i.e. the ratio between phi(M)*N^rank(G) and the degree of Q_{M,N}
82over Q, is given by the (i,j)-th entry of the table for i=gcd(N,N_0) and
83j=gcd(M,M_0).
84
85In case -1 belongs to G, we need to distinguish two cases, depending on the
86parity of M/N. The two tables are similar to the case described
87above, and can be seen in the example below.
88
89The output includes an explanation of the tables and how to read them to
90deduce the actual degrees (that can be computed with KummerDegree).
91
92EXAMPLES:
67 93
68``` 94```
95sage: TotalKummerFailure([-36,12])
96M_0 = 24
97N_0 = 8
69 98
99The following table shows the total failure of Kummer degrees.
100The degree of the Kummer extension (M,N) is e / f, where e = phi(M)*N^rank(G)
101and f is the entry of the table below at the row labelled with gcd(N,N0) and
102the 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```
70sage: TotalKummerFailure([-36,12,-1]) 114sage: TotalKummerFailure([-36,12,-1])
71M_0 = 24 115M_0 = 24
72N_0 = 8 116N_0 = 8
73 117
74The following table shows the total failure of Kummer degrees in case the quotient M/N is EVEN. 118The following table shows the total failure of Kummer degrees in case the
75The 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). 119quotient M/N is EVEN.
120The degree of the Kummer extension (M,N) is e / f, where e = phi(M)*N^rank(G)
121if N is odd and e = 2*phi(M)*N^rank(G) if N is even and f is the entry of the
122table below at the row labelled with gcd(N,N0) and the column labelled with
123gcd(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
84The following table shows the total failure of Kummer degrees if the quotient M/N is ODD and is read as the previous one. 132The following table shows the total failure of Kummer degrees if the quotient
133M/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

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