Properties

Label 2.2.8.62a1.218
Base \(\Q_{2}\)
Degree \(16\)
e \(8\)
f \(2\)
c \(62\)
Galois group $C_4^2:D_4$ (as 16T359)

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Defining polynomial

$( x^{2} + x + 1 )^{8} + 8 ( x^{2} + x + 1 )^{7} + 8 x ( x^{2} + x + 1 )^{6} + 16 ( x^{2} + x + 1 )^{5} + 16 ( x^{2} + x + 1 )^{3} + 16 x + 2$ Copy content Toggle raw display

Invariants

Base field: $\Q_{2}$
Degree $d$: $16$
Ramification index $e$: $8$
Residue field degree $f$: $2$
Discriminant exponent $c$: $62$
Discriminant root field: $\Q_{2}$
Root number: $-1$
$\Aut(K/\Q_{2})$: $C_2$
This field is not Galois over $\Q_{2}.$
Visible Artin slopes:$[3, 4, 5]$
Visible Swan slopes:$[2,3,4]$
Means:$\langle1, 2, 3\rangle$
Rams:$(2, 4, 8)$
Jump set:$[1, 3, 7, 15]$
Roots of unity:$6 = (2^{ 2 } - 1) \cdot 2$

Intermediate fields

$\Q_{2}(\sqrt{5})$, $\Q_{2}(\sqrt{-2})$, $\Q_{2}(\sqrt{-2\cdot 5})$, 2.2.2.6a1.1, 2.1.4.11a1.5, 2.1.4.11a1.6, 2.2.4.22a1.4

Fields in the database are given up to isomorphism. Isomorphic intermediate fields are shown with their multiplicities.

Canonical tower

Unramified subfield:$\Q_{2}(\sqrt{5})$ $\cong \Q_{2}(t)$ where $t$ is a root of \( x^{2} + x + 1 \) Copy content Toggle raw display
Relative Eisenstein polynomial: \( x^{8} + 16 t x^{7} + \left(8 t + 8\right) x^{6} + 16 x^{3} + 16 x + 16 t + 2 \) $\ \in\Q_{2}(t)[x]$ Copy content Toggle raw display

Ramification polygon

Residual polynomials:$z^4 + 1$,$z^2 + 1$,$z + 1$
Associated inertia:$1$,$1$,$1$
Indices of inseparability:$[24, 16, 8, 0]$

Invariants of the Galois closure

Galois degree: $128$
Galois group: $C_4^2:D_4$ (as 16T359)
Inertia group: Intransitive group isomorphic to $C_2\wr C_4$
Wild inertia group: $C_2\wr C_4$
Galois unramified degree: $2$
Galois tame degree: $1$
Galois Artin slopes: $[2, 3, \frac{7}{2}, 4, \frac{17}{4}, 5]$
Galois Swan slopes: $[1,2,\frac{5}{2},3,\frac{13}{4},4]$
Galois mean slope: $4.40625$
Galois splitting model:$x^{16} - 4 x^{12} + 66 x^{8} - 288 x^{6} + 1928 x^{4} - 3600 x^{2} + 2500$