Basic invariants
| Dimension: | $2$ |
| Group: | $D_4$ |
| Conductor: | \(155\)\(\medspace = 5 \cdot 31 \) |
| Frobenius-Schur indicator: | $1$ |
| Root number: | $1$ |
| Artin field: | Galois closure of 8.0.577200625.1 |
| Galois orbit size: | $1$ |
| Smallest permutation container: | $D_{4}$ |
| Parity: | odd |
| Determinant: | 1.155.2t1.a.a |
| Projective image: | $C_2^2$ |
| Projective field: | Galois closure of \(\Q(\sqrt{5}, \sqrt{-31})\) |
Defining polynomial
| $f(x)$ | $=$ |
\( x^{8} - 5x^{6} + 32x^{4} - 45x^{2} + 81 \)
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The roots of $f$ are computed in $\Q_{ 41 }$ to precision 5.
Roots:
| $r_{ 1 }$ | $=$ |
\( 9 + 30\cdot 41 + 24\cdot 41^{2} + 12\cdot 41^{3} + 39\cdot 41^{4} +O(41^{5})\)
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| $r_{ 2 }$ | $=$ |
\( 13 + 10\cdot 41 + 13\cdot 41^{3} + 20\cdot 41^{4} +O(41^{5})\)
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| $r_{ 3 }$ | $=$ |
\( 14 + 35\cdot 41 + 8\cdot 41^{2} + 35\cdot 41^{3} + 10\cdot 41^{4} +O(41^{5})\)
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| $r_{ 4 }$ | $=$ |
\( 16 + 22\cdot 41 + 39\cdot 41^{2} + 22\cdot 41^{3} + 41^{4} +O(41^{5})\)
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| $r_{ 5 }$ | $=$ |
\( 25 + 18\cdot 41 + 41^{2} + 18\cdot 41^{3} + 39\cdot 41^{4} +O(41^{5})\)
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| $r_{ 6 }$ | $=$ |
\( 27 + 5\cdot 41 + 32\cdot 41^{2} + 5\cdot 41^{3} + 30\cdot 41^{4} +O(41^{5})\)
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| $r_{ 7 }$ | $=$ |
\( 28 + 30\cdot 41 + 40\cdot 41^{2} + 27\cdot 41^{3} + 20\cdot 41^{4} +O(41^{5})\)
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| $r_{ 8 }$ | $=$ |
\( 32 + 10\cdot 41 + 16\cdot 41^{2} + 28\cdot 41^{3} + 41^{4} +O(41^{5})\)
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Generators of the action on the roots $r_1, \ldots, r_{ 8 }$
| Cycle notation |
Character values on conjugacy classes
| Size | Order | Action on $r_1, \ldots, r_{ 8 }$ | Character value |
| $1$ | $1$ | $()$ | $2$ |
| $1$ | $2$ | $(1,8)(2,7)(3,6)(4,5)$ | $-2$ |
| $2$ | $2$ | $(1,3)(2,5)(4,7)(6,8)$ | $0$ |
| $2$ | $2$ | $(1,5)(2,6)(3,7)(4,8)$ | $0$ |
| $2$ | $4$ | $(1,2,8,7)(3,4,6,5)$ | $0$ |
The blue line marks the conjugacy class containing complex conjugation.