Properties

Label 2.5e2_79.8t8.1
Dimension 2
Group $QD_{16}$
Conductor $ 5^{2} \cdot 79 $
Frobenius-Schur indicator 0

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Basic invariants

Dimension:$2$
Group:$QD_{16}$
Conductor:$1975= 5^{2} \cdot 79 $
Artin number field: Splitting field of $f= x^{8} - 2 x^{7} - x^{6} + 2 x^{5} - 4 x^{4} - 20 x^{3} - 30 x^{2} - 20 x - 5 $ over $\Q$
Size of Galois orbit: 2
Smallest containing permutation representation: $QD_{16}$
Parity: Odd

Galois action

Roots of defining polynomial

The roots of $f$ are computed in $\Q_{ 101 }$ to precision 5.
Roots:
$r_{ 1 }$ $=$ $ 14 + 53\cdot 101 + 89\cdot 101^{2} + 101^{3} + 95\cdot 101^{4} +O\left(101^{ 5 }\right)$
$r_{ 2 }$ $=$ $ 26 + 39\cdot 101 + 71\cdot 101^{2} + 24\cdot 101^{3} + 29\cdot 101^{4} +O\left(101^{ 5 }\right)$
$r_{ 3 }$ $=$ $ 27 + 42\cdot 101 + 10\cdot 101^{2} + 89\cdot 101^{3} + 94\cdot 101^{4} +O\left(101^{ 5 }\right)$
$r_{ 4 }$ $=$ $ 38 + 34\cdot 101 + 93\cdot 101^{2} + 52\cdot 101^{3} + 95\cdot 101^{4} +O\left(101^{ 5 }\right)$
$r_{ 5 }$ $=$ $ 56 + 87\cdot 101 + 7\cdot 101^{2} + 76\cdot 101^{3} + 3\cdot 101^{4} +O\left(101^{ 5 }\right)$
$r_{ 6 }$ $=$ $ 66 + 74\cdot 101 + 2\cdot 101^{2} + 68\cdot 101^{3} + 29\cdot 101^{4} +O\left(101^{ 5 }\right)$
$r_{ 7 }$ $=$ $ 82 + 37\cdot 101 + 90\cdot 101^{2} + 84\cdot 101^{3} + 7\cdot 101^{4} +O\left(101^{ 5 }\right)$
$r_{ 8 }$ $=$ $ 97 + 34\cdot 101 + 38\cdot 101^{2} + 6\cdot 101^{3} + 48\cdot 101^{4} +O\left(101^{ 5 }\right)$

Generators of the action on the roots $r_1, \ldots, r_{ 8 }$

Cycle notation
$(1,8)(2,6)(4,5)$
$(1,8,2,6)(3,4,7,5)$
$(1,2)(3,7)(4,5)(6,8)$
$(1,7,2,3)(4,6,5,8)$

Character values on conjugacy classes

SizeOrderAction on $r_1, \ldots, r_{ 8 }$ Character values
$c1$ $c2$
$1$ $1$ $()$ $2$ $2$
$1$ $2$ $(1,2)(3,7)(4,5)(6,8)$ $-2$ $-2$
$4$ $2$ $(1,8)(2,6)(4,5)$ $0$ $0$
$2$ $4$ $(1,8,2,6)(3,4,7,5)$ $0$ $0$
$4$ $4$ $(1,7,2,3)(4,6,5,8)$ $0$ $0$
$2$ $8$ $(1,7,6,4,2,3,8,5)$ $-\zeta_{8}^{3} - \zeta_{8}$ $\zeta_{8}^{3} + \zeta_{8}$
$2$ $8$ $(1,3,6,5,2,7,8,4)$ $\zeta_{8}^{3} + \zeta_{8}$ $-\zeta_{8}^{3} - \zeta_{8}$
The blue line marks the conjugacy class containing complex conjugation.