Properties

Label 2.5_19.8t6.2c2
Dimension 2
Group $D_{8}$
Conductor $ 5 \cdot 19 $
Root number 1
Frobenius-Schur indicator 1

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Basic invariants

Dimension:$2$
Group:$D_{8}$
Conductor:$95= 5 \cdot 19 $
Artin number field: Splitting field of $f= x^{8} - x^{7} - x^{6} + 4 x^{5} + x^{4} - 4 x^{3} - x^{2} + x + 1 $ over $\Q$
Size of Galois orbit: 2
Smallest containing permutation representation: $D_{8}$
Parity: Odd
Determinant: 1.5_19.2t1.1c1

Galois action

Roots of defining polynomial

The roots of $f$ are computed in $\Q_{ 131 }$ to precision 5.
Roots:
$r_{ 1 }$ $=$ $ 3 + 87\cdot 131 + 44\cdot 131^{2} + 26\cdot 131^{3} + 31\cdot 131^{4} +O\left(131^{ 5 }\right)$
$r_{ 2 }$ $=$ $ 19 + 95\cdot 131 + 73\cdot 131^{2} + 102\cdot 131^{3} + 92\cdot 131^{4} +O\left(131^{ 5 }\right)$
$r_{ 3 }$ $=$ $ 22 + 74\cdot 131 + 38\cdot 131^{2} + 59\cdot 131^{3} + 16\cdot 131^{4} +O\left(131^{ 5 }\right)$
$r_{ 4 }$ $=$ $ 36 + 6\cdot 131 + 8\cdot 131^{2} + 110\cdot 131^{3} + 108\cdot 131^{4} +O\left(131^{ 5 }\right)$
$r_{ 5 }$ $=$ $ 40 + 84\cdot 131 + 31\cdot 131^{2} + 10\cdot 131^{3} + 83\cdot 131^{4} +O\left(131^{ 5 }\right)$
$r_{ 6 }$ $=$ $ 62 + 117\cdot 131 + 125\cdot 131^{2} + 116\cdot 131^{3} + 13\cdot 131^{4} +O\left(131^{ 5 }\right)$
$r_{ 7 }$ $=$ $ 87 + 9\cdot 131 + 103\cdot 131^{2} + 88\cdot 131^{3} + 39\cdot 131^{4} +O\left(131^{ 5 }\right)$
$r_{ 8 }$ $=$ $ 125 + 49\cdot 131 + 98\cdot 131^{2} + 9\cdot 131^{3} + 7\cdot 131^{4} +O\left(131^{ 5 }\right)$

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

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

Character values on conjugacy classes

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