Properties

Label 2.2e7_7.8t6.4c2
Dimension 2
Group $D_{8}$
Conductor $ 2^{7} \cdot 7 $
Root number 1
Frobenius-Schur indicator 1

Related objects

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Basic invariants

Dimension:$2$
Group:$D_{8}$
Conductor:$896= 2^{7} \cdot 7 $
Artin number field: Splitting field of $f= x^{8} + 4 x^{6} + 5 x^{4} + 2 x^{2} + 2 $ over $\Q$
Size of Galois orbit: 2
Smallest containing permutation representation: $D_{8}$
Parity: Odd
Determinant: 1.2e3_7.2t1.2c1

Galois action

Roots of defining polynomial

The roots of $f$ are computed in $\Q_{ 191 }$ to precision 5.
Roots:
$r_{ 1 }$ $=$ $ 40 + 28\cdot 191 + 2\cdot 191^{2} + 182\cdot 191^{3} + 57\cdot 191^{4} +O\left(191^{ 5 }\right)$
$r_{ 2 }$ $=$ $ 58 + 155\cdot 191 + 16\cdot 191^{2} + 65\cdot 191^{3} + 76\cdot 191^{4} +O\left(191^{ 5 }\right)$
$r_{ 3 }$ $=$ $ 60 + 38\cdot 191 + 128\cdot 191^{2} + 36\cdot 191^{3} + 117\cdot 191^{4} +O\left(191^{ 5 }\right)$
$r_{ 4 }$ $=$ $ 72 + 98\cdot 191 + 121\cdot 191^{2} + 20\cdot 191^{3} + 150\cdot 191^{4} +O\left(191^{ 5 }\right)$
$r_{ 5 }$ $=$ $ 119 + 92\cdot 191 + 69\cdot 191^{2} + 170\cdot 191^{3} + 40\cdot 191^{4} +O\left(191^{ 5 }\right)$
$r_{ 6 }$ $=$ $ 131 + 152\cdot 191 + 62\cdot 191^{2} + 154\cdot 191^{3} + 73\cdot 191^{4} +O\left(191^{ 5 }\right)$
$r_{ 7 }$ $=$ $ 133 + 35\cdot 191 + 174\cdot 191^{2} + 125\cdot 191^{3} + 114\cdot 191^{4} +O\left(191^{ 5 }\right)$
$r_{ 8 }$ $=$ $ 151 + 162\cdot 191 + 188\cdot 191^{2} + 8\cdot 191^{3} + 133\cdot 191^{4} +O\left(191^{ 5 }\right)$

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

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

Character values on conjugacy classes

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