Elliptic curve with LMFDB label 1600.o2 (Cremona label 1600a2)

• Label: 1600.o2
• Conductor: $1600$
• Discriminant: $6400000000$
• j-invariant: $\frac{148176}{25}$
• CM: no
• Rank: $1$
• Torsion structure: $\Z/{2}\Z \oplus \Z/{2}\Z$

Minimal Weierstrass equation

$y^2=x^3-700x-6000$

(, )

Mordell-Weil group structure

$\Z \oplus \Z/{2}\Z \oplus \Z/{2}\Z$

Mordell-Weil generators

$P$	$\hat{h}(P)$	Order
$(-19, 21)$	$3.0969466034384661090778561949$	$\infty$
$(-10, 0)$	$0$	$2$
$(30, 0)$	$0$	$2$

Integral points

$\left(-20, 0\right)$, $(-19,\pm 21)$, $\left(-10, 0\right)$, $\left(30, 0\right)$, $(480,\pm 10500)$

Invariants

Conductor:	$N$	=	$1600$	=	$2^{6} \cdot 5^{2}$
Discriminant:	$\Delta$	=	$6400000000$	=	$2^{14} \cdot 5^{8}$
j-invariant:	$j$	=	$\frac{148176}{25}$	=	$2^{4} \cdot 3^{3} \cdot 5^{-2} \cdot 7^{3}$
Endomorphism ring:	$\mathrm{End}(E)$	=	$\Z$
Geometric endomorphism ring:	$\mathrm{End}(E_{\overline{\Q}})$	=	$\Z$    (no potential complex multiplication)
Sato-Tate group:	$\mathrm{ST}(E)$	=	$\mathrm{SU}(2)$
Faltings height:	$h_{\mathrm{Faltings}}$	≈	$0.60250517422086027456189973040$
Stable Faltings height:	$h_{\mathrm{stable}}$	≈	$-1.0108854926494594403919174112$
$abc$ quality:	$Q$	≈	$1.0917548251330267$
Szpiro ratio:	$\sigma_{m}$	≈	$4.237986687662601$

BSD invariants

Analytic rank:	$r_{\mathrm{an}}$	=	$1$
Mordell-Weil rank:	$r$	=	$1$
Regulator:	$\mathrm{Reg}(E/\Q)$	≈	$3.0969466034384661090778561949$
Real period:	$\Omega$	≈	$0.93882488063578016092024447501$
Tamagawa product:	$\prod_{p}c_p$	=	$16$  = $2^{2}\cdot2^{2}$
Torsion order:	$\#E(\Q)_{\mathrm{tor}}$	=	$4$
Special value:	$L'(E,1)$	≈	$2.9074905253085027421345977870$
Analytic order of Ш:	Ш${}_{\mathrm{an}}$	≈	$1$    (rounded)

BSD formula

$\begin{aligned} 2.907490525 \approx L'(E,1) & = \frac{\# Ш(E/\Q)\cdot \Omega_E \cdot \mathrm{Reg}(E/\Q) \cdot \prod_p c_p}{\#E(\Q)_{\rm tor}^2} \\ & \approx \frac{1 \cdot 0.938825 \cdot 3.096947 \cdot 16}{4^2} \\ & \approx 2.907490525\end{aligned}$

Modular invariants

Modular form   1600.2.a.o

$q + 4 q^{7} - 3 q^{9} - 4 q^{11} - 2 q^{13} - 2 q^{17} - 4 q^{19} + O(q^{20})$

For more coefficients, see the Downloads section to the right.

Modular degree:	768
$\Gamma_0(N)$-optimal:	no
Manin constant:	1

Local data at primes of bad reduction

This elliptic curve is not semistable. There are 2 primes $p$ of bad reduction:

$p$	Tamagawa number	Kodaira symbol	Reduction type	Root number	$\mathrm{ord}_p(N)$	$\mathrm{ord}_p(\Delta)$	$\mathrm{ord}_p(\mathrm{den}(j))$
$2$	$4$	$I_{4}^{*}$	additive	1	6	14	0
$5$	$4$	$I_{2}^{*}$	additive	1	2	8	2

Galois representations

The $\ell$-adic Galois representation has maximal image for all primes $\ell$ except those listed in the table below.

prime $\ell$	mod-$\ell$ image	$\ell$-adic image
$2$	2Cs	8.48.0.149

The image $H:=\rho_E(\Gal(\overline{\Q}/\Q))$ of the adelic Galois representation has label 40.192.3-40.bk.1.3, level $40 = 2^{3} \cdot 5$, index $192$, genus $3$, and generators

$\left(\begin{array}{rr} 21 & 8 \\ 0 & 11 \end{array}\right),\left(\begin{array}{rr} 1 & 34 \\ 22 & 5 \end{array}\right),\left(\begin{array}{rr} 15 & 36 \\ 24 & 19 \end{array}\right),\left(\begin{array}{rr} 33 & 8 \\ 32 & 9 \end{array}\right),\left(\begin{array}{rr} 1 & 0 \\ 8 & 1 \end{array}\right),\left(\begin{array}{rr} 1 & 4 \\ 4 & 17 \end{array}\right),\left(\begin{array}{rr} 1 & 8 \\ 0 & 1 \end{array}\right)$.

The torsion field $K:=\Q(E[40])$ is a degree-$3840$ Galois extension of $\Q$ with $\Gal(K/\Q)$ isomorphic to the projection of $H$ to $\GL_2(\Z/40\Z)$.

The table below list all primes $\ell$ for which the Serre invariants associated to the mod-$\ell$ Galois representation are exceptional.

$\ell$	Reduction type	Serre weight	Serre conductor
$2$	additive	$2$	$25 = 5^{2}$
$5$	additive	$18$	$64 = 2^{6}$

Isogenies

This curve has non-trivial cyclic isogenies of degree $d$ for $d=$ 2.
Its isogeny class 1600.o consists of 4 curves linked by isogenies of degrees dividing 4.

Twists

The minimal quadratic twist of this elliptic curve is 40.a2, its twist by $40$.

Growth of torsion in number fields

The number fields $K$ of degree less than 24 such that $E(K)_{\rm tors}$ is strictly larger than $E(\Q)_{\rm tors}$ $\cong \Z/{2}\Z \oplus \Z/{2}\Z$ are as follows:

$[K:\Q]$	$K$	$E(K)_{\rm tors}$	Base change curve
$4$	$\Q(\sqrt{2}, \sqrt{5})$	$\Z/2\Z \oplus \Z/4\Z$	not in database
$4$	$\Q(\sqrt{-2}, \sqrt{5})$	$\Z/2\Z \oplus \Z/4\Z$	not in database
$4$	$\Q(i, \sqrt{10})$	$\Z/2\Z \oplus \Z/4\Z$	not in database
$8$	8.0.40960000.1	$\Z/4\Z \oplus \Z/4\Z$	not in database
$8$	8.0.163840000.2	$\Z/2\Z \oplus \Z/8\Z$	not in database
$8$	8.2.2239488000000.10	$\Z/2\Z \oplus \Z/6\Z$	not in database
$16$	16.8.16777216000000000000.1	$\Z/2\Z \oplus \Z/8\Z$	not in database
$16$	16.0.1048576000000000000.4	$\Z/2\Z \oplus \Z/8\Z$	not in database
$16$	16.0.26843545600000000.2	$\Z/4\Z \oplus \Z/8\Z$	not in database

We only show fields where the torsion growth is primitive.

Iwasawa invariants

$p$	2	3	5	7	11	13	17	19	23	29	31	37	41	43	47
Reduction type	add	ss	add	ord	ord	ord	ord	ord	ord	ord	ord	ord	ord	ord	ord
$\lambda$-invariant(s)	-	1,1	-	1	1	1	1	1	1	1	1	1	3	1	1
$\mu$-invariant(s)	-	0,0	-	0	0	0	0	0	0	0	0	0	0	0	0

An entry - indicates that the invariants are not computed because the reduction is additive.

$p$-adic regulators

$p$-adic regulators are not yet computed for curves that are not $\Gamma_0$-optimal.