Properties

Label 2.2e3_139.7t2.1
Dimension 2
Group $D_{7}$
Conductor $ 2^{3} \cdot 139 $
Frobenius-Schur indicator 1

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Basic invariants

Dimension:$2$
Group:$D_{7}$
Conductor:$1112= 2^{3} \cdot 139 $
Artin number field: Splitting field of $f= x^{7} - 3 x^{6} + 7 x^{5} - 5 x^{4} + 6 x^{3} + 18 x^{2} - 16 x + 32 $ over $\Q$
Size of Galois orbit: 3
Smallest containing permutation representation: $D_{7}$
Parity: Odd

Galois action

Roots of defining polynomial

The roots of $f$ are computed in an extension of $\Q_{ 11 }$ to precision 5.
Minimal polynomial of a generator $a$ of $K$ over $\mathbb{Q}_{ 11 }$: $ x^{2} + 7 x + 2 $
Roots:
$r_{ 1 }$ $=$ $ 10 + 8\cdot 11 + 5\cdot 11^{2} + 9\cdot 11^{4} +O\left(11^{ 5 }\right)$
$r_{ 2 }$ $=$ $ 8 a + 8 + \left(3 a + 4\right)\cdot 11 + \left(9 a + 2\right)\cdot 11^{2} + \left(7 a + 8\right)\cdot 11^{3} + \left(3 a + 4\right)\cdot 11^{4} +O\left(11^{ 5 }\right)$
$r_{ 3 }$ $=$ $ 7 a + \left(2 a + 1\right)\cdot 11 + 9 a\cdot 11^{2} + \left(10 a + 5\right)\cdot 11^{3} + \left(10 a + 6\right)\cdot 11^{4} +O\left(11^{ 5 }\right)$
$r_{ 4 }$ $=$ $ 10 a + 10 + \left(4 a + 1\right)\cdot 11 + 3 a\cdot 11^{2} + \left(a + 7\right)\cdot 11^{3} + \left(a + 6\right)\cdot 11^{4} +O\left(11^{ 5 }\right)$
$r_{ 5 }$ $=$ $ 3 a + 7 + 7 a\cdot 11 + \left(a + 3\right)\cdot 11^{2} + \left(3 a + 8\right)\cdot 11^{3} + 7 a\cdot 11^{4} +O\left(11^{ 5 }\right)$
$r_{ 6 }$ $=$ $ 4 a + 6 + \left(8 a + 4\right)\cdot 11 + \left(a + 1\right)\cdot 11^{2} + 6\cdot 11^{3} + 6\cdot 11^{4} +O\left(11^{ 5 }\right)$
$r_{ 7 }$ $=$ $ a + 6 + 6 a\cdot 11 + \left(7 a + 9\right)\cdot 11^{2} + \left(9 a + 8\right)\cdot 11^{3} + \left(9 a + 9\right)\cdot 11^{4} +O\left(11^{ 5 }\right)$

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

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

Character values on conjugacy classes

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