Properties

Label 2.2e4_17.8t6.2
Dimension 2
Group $D_{8}$
Conductor $ 2^{4} \cdot 17 $
Frobenius-Schur indicator 1

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Basic invariants

Dimension:$2$
Group:$D_{8}$
Conductor:$272= 2^{4} \cdot 17 $
Artin number field: Splitting field of $f= x^{8} - 2 x^{7} - 2 x^{6} + 2 x^{5} + 6 x^{4} - 6 x^{3} + 6 x^{2} - 2 x + 1 $ over $\Q$
Size of Galois orbit: 2
Smallest containing permutation representation: $D_{8}$
Parity: Odd

Galois action

Roots of defining polynomial

The roots of $f$ are computed in $\Q_{ 149 }$ to precision 5.
Roots:
$r_{ 1 }$ $=$ $ 8 + 45\cdot 149 + 19\cdot 149^{2} + 12\cdot 149^{3} + 127\cdot 149^{4} +O\left(149^{ 5 }\right)$
$r_{ 2 }$ $=$ $ 15 + 66\cdot 149 + 22\cdot 149^{2} + 90\cdot 149^{3} + 45\cdot 149^{4} +O\left(149^{ 5 }\right)$
$r_{ 3 }$ $=$ $ 18 + 24\cdot 149 + 58\cdot 149^{2} + 63\cdot 149^{3} + 41\cdot 149^{4} +O\left(149^{ 5 }\right)$
$r_{ 4 }$ $=$ $ 19 + 7\cdot 149 + 47\cdot 149^{2} + 43\cdot 149^{3} + 127\cdot 149^{4} +O\left(149^{ 5 }\right)$
$r_{ 5 }$ $=$ $ 38 + 137\cdot 149 + 80\cdot 149^{2} + 15\cdot 149^{3} + 100\cdot 149^{4} +O\left(149^{ 5 }\right)$
$r_{ 6 }$ $=$ $ 69 + 4\cdot 149 + 142\cdot 149^{2} + 43\cdot 149^{3} + 140\cdot 149^{4} +O\left(149^{ 5 }\right)$
$r_{ 7 }$ $=$ $ 140 + 122\cdot 149 + 21\cdot 149^{2} + 134\cdot 149^{3} + 92\cdot 149^{4} +O\left(149^{ 5 }\right)$
$r_{ 8 }$ $=$ $ 142 + 39\cdot 149 + 55\cdot 149^{2} + 44\cdot 149^{3} + 70\cdot 149^{4} +O\left(149^{ 5 }\right)$

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

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

Character values on conjugacy classes

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