Properties

Label 2.391.7t2.a
Dimension $2$
Group $D_{7}$
Conductor $391$
Indicator $1$

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Basic invariants

Dimension:$2$
Group:$D_{7}$
Conductor:\(391\)\(\medspace = 17 \cdot 23 \)
Frobenius-Schur indicator: $1$
Root number: $1$
Artin number field: Galois closure of 7.1.59776471.1
Galois orbit size: $3$
Smallest permutation container: $D_{7}$
Parity: odd
Projective image: $D_7$
Projective field: Galois closure of 7.1.59776471.1

Galois action

Roots of defining polynomial

The roots of $f$ are computed in an extension of $\Q_{ 19 }$ to precision 5.
Minimal polynomial of a generator $a$ of $K$ over $\mathbb{Q}_{ 19 }$: \( x^{2} + 18x + 2 \) Copy content Toggle raw display
Roots:
$r_{ 1 }$ $=$ \( a + 17 + \left(8 a + 4\right)\cdot 19 + \left(12 a + 18\right)\cdot 19^{2} + \left(3 a + 9\right)\cdot 19^{3} + \left(16 a + 18\right)\cdot 19^{4} +O(19^{5})\) Copy content Toggle raw display
$r_{ 2 }$ $=$ \( 7 a + 9 + \left(4 a + 3\right)\cdot 19 + \left(3 a + 4\right)\cdot 19^{2} + \left(10 a + 6\right)\cdot 19^{3} + \left(15 a + 9\right)\cdot 19^{4} +O(19^{5})\) Copy content Toggle raw display
$r_{ 3 }$ $=$ \( 18 a + 18 + \left(10 a + 11\right)\cdot 19 + \left(6 a + 3\right)\cdot 19^{2} + \left(15 a + 1\right)\cdot 19^{3} + \left(2 a + 12\right)\cdot 19^{4} +O(19^{5})\) Copy content Toggle raw display
$r_{ 4 }$ $=$ \( 3 a + 4 + \left(7 a + 3\right)\cdot 19 + \left(12 a + 13\right)\cdot 19^{2} + 2\cdot 19^{3} + \left(14 a + 7\right)\cdot 19^{4} +O(19^{5})\) Copy content Toggle raw display
$r_{ 5 }$ $=$ \( 7 + 6\cdot 19 + 15\cdot 19^{2} + 13\cdot 19^{3} + 12\cdot 19^{4} +O(19^{5})\) Copy content Toggle raw display
$r_{ 6 }$ $=$ \( 12 a + 16 + 14 a\cdot 19 + \left(15 a + 3\right)\cdot 19^{2} + \left(8 a + 13\right)\cdot 19^{3} + \left(3 a + 14\right)\cdot 19^{4} +O(19^{5})\) Copy content Toggle raw display
$r_{ 7 }$ $=$ \( 16 a + 7 + \left(11 a + 7\right)\cdot 19 + \left(6 a + 18\right)\cdot 19^{2} + \left(18 a + 9\right)\cdot 19^{3} + \left(4 a + 1\right)\cdot 19^{4} +O(19^{5})\) Copy content Toggle raw display

Generators of the action on the roots $r_1, \ldots, r_{ 7 }$

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

Character values on conjugacy classes

SizeOrderAction on $r_1, \ldots, r_{ 7 }$ Character values
$c1$ $c2$ $c3$
$1$ $1$ $()$ $2$ $2$ $2$
$7$ $2$ $(1,7)(2,3)(4,5)$ $0$ $0$ $0$
$2$ $7$ $(1,5,3,2,4,7,6)$ $-\zeta_{7}^{5} - \zeta_{7}^{4} - \zeta_{7}^{3} - \zeta_{7}^{2} - 1$ $\zeta_{7}^{4} + \zeta_{7}^{3}$ $\zeta_{7}^{5} + \zeta_{7}^{2}$
$2$ $7$ $(1,3,4,6,5,2,7)$ $\zeta_{7}^{5} + \zeta_{7}^{2}$ $-\zeta_{7}^{5} - \zeta_{7}^{4} - \zeta_{7}^{3} - \zeta_{7}^{2} - 1$ $\zeta_{7}^{4} + \zeta_{7}^{3}$
$2$ $7$ $(1,2,6,3,7,5,4)$ $\zeta_{7}^{4} + \zeta_{7}^{3}$ $\zeta_{7}^{5} + \zeta_{7}^{2}$ $-\zeta_{7}^{5} - \zeta_{7}^{4} - \zeta_{7}^{3} - \zeta_{7}^{2} - 1$
The blue line marks the conjugacy class containing complex conjugation.