Properties

Label 2.2e8_5e2.8t7.1
Dimension 2
Group $C_8:C_2$
Conductor $ 2^{8} \cdot 5^{2}$
Frobenius-Schur indicator 0

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Basic invariants

Dimension:$2$
Group:$C_8:C_2$
Conductor:$6400= 2^{8} \cdot 5^{2} $
Artin number field: Splitting field of $f= x^{8} - 20 x^{6} + 130 x^{4} - 280 x^{2} + 20 $ over $\Q$
Size of Galois orbit: 2
Smallest containing permutation representation: $C_8:C_2$
Parity: Even

Galois action

Roots of defining polynomial

The roots of $f$ are computed in $\Q_{ 41 }$ to precision 9.
Roots:
$r_{ 1 }$ $=$ $ 8 + 28\cdot 41 + 19\cdot 41^{2} + 40\cdot 41^{3} + 5\cdot 41^{4} + 26\cdot 41^{5} + 27\cdot 41^{6} + 15\cdot 41^{7} + 21\cdot 41^{8} +O\left(41^{ 9 }\right)$
$r_{ 2 }$ $=$ $ 9 + 34\cdot 41 + 37\cdot 41^{2} + 41^{3} + 24\cdot 41^{4} + 4\cdot 41^{5} + 16\cdot 41^{6} + 20\cdot 41^{7} + 26\cdot 41^{8} +O\left(41^{ 9 }\right)$
$r_{ 3 }$ $=$ $ 17 + 31\cdot 41 + 28\cdot 41^{2} + 16\cdot 41^{3} + 11\cdot 41^{4} + 4\cdot 41^{5} + 8\cdot 41^{6} + 25\cdot 41^{7} + 17\cdot 41^{8} +O\left(41^{ 9 }\right)$
$r_{ 4 }$ $=$ $ 18 + 32\cdot 41^{2} + 21\cdot 41^{3} + 23\cdot 41^{4} + 18\cdot 41^{5} + 33\cdot 41^{6} + 18\cdot 41^{7} + 36\cdot 41^{8} +O\left(41^{ 9 }\right)$
$r_{ 5 }$ $=$ $ 23 + 40\cdot 41 + 8\cdot 41^{2} + 19\cdot 41^{3} + 17\cdot 41^{4} + 22\cdot 41^{5} + 7\cdot 41^{6} + 22\cdot 41^{7} + 4\cdot 41^{8} +O\left(41^{ 9 }\right)$
$r_{ 6 }$ $=$ $ 24 + 9\cdot 41 + 12\cdot 41^{2} + 24\cdot 41^{3} + 29\cdot 41^{4} + 36\cdot 41^{5} + 32\cdot 41^{6} + 15\cdot 41^{7} + 23\cdot 41^{8} +O\left(41^{ 9 }\right)$
$r_{ 7 }$ $=$ $ 32 + 6\cdot 41 + 3\cdot 41^{2} + 39\cdot 41^{3} + 16\cdot 41^{4} + 36\cdot 41^{5} + 24\cdot 41^{6} + 20\cdot 41^{7} + 14\cdot 41^{8} +O\left(41^{ 9 }\right)$
$r_{ 8 }$ $=$ $ 33 + 12\cdot 41 + 21\cdot 41^{2} + 35\cdot 41^{4} + 14\cdot 41^{5} + 13\cdot 41^{6} + 25\cdot 41^{7} + 19\cdot 41^{8} +O\left(41^{ 9 }\right)$

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

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

Character values on conjugacy classes

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