Elliptic curve isogeny class with Cremona label 91b (LMFDB label 91.b)

• Label: 91b
• Number of curves: $3$
• Conductor: $91$
• CM: no
• Rank: $1$

Rank

The elliptic curves in class 91b have rank \(1\).

L-function data

Bad L-factors:

Prime	L-Factor
\(7\)	\(1 - T\)
\(13\)	\(1 - T\)

Good L-factors:

Prime	L-Factor	Isogeny Class over \(\mathbb{F}_p\)
\(2\)	\( 1 + 2 T^{2}\)	1.2.a
\(3\)	\( 1 + 2 T + 3 T^{2}\)	1.3.c
\(5\)	\( 1 + 3 T + 5 T^{2}\)	1.5.d
\(11\)	\( 1 + 11 T^{2}\)	1.11.a
\(17\)	\( 1 + 6 T + 17 T^{2}\)	1.17.g
\(19\)	\( 1 + 7 T + 19 T^{2}\)	1.19.h
\(23\)	\( 1 - 3 T + 23 T^{2}\)	1.23.ad
\(29\)	\( 1 + 9 T + 29 T^{2}\)	1.29.j
$\cdots$	$\cdots$	$\cdots$

See L-function page for more information

Complex multiplication

The elliptic curves in class 91b do not have complex multiplication.

Modular form 91.2.a.b

Isogeny matrix

The \(i,j\) entry is the smallest degree of a cyclic isogeny between the \(i\)-th and \(j\)-th curve in the isogeny class, in the Cremona numbering.

\(\left(\begin{array}{rrr} 1 & 3 & 9 \\ 3 & 1 & 3 \\ 9 & 3 & 1 \end{array}\right)\)

Isogeny graph

The vertices are labelled with Cremona labels.

Elliptic curves in class 91b

LMFDB label	Cremona label	Weierstrass coefficients	j-invariant	Discriminant	Torsion structure	Modular degree	Faltings height	Optimality
91.b2	91b1	\([0, 1, 1, -7, 5]\)	\(-43614208/91\)	\(-91\)	\([3]\)	\(4\)	\(-0.73851\)	\(\Gamma_0(N)\)-optimal
91.b3	91b2	\([0, 1, 1, 13, 42]\)	\(224755712/753571\)	\(-753571\)	\([3]\)	\(12\)	\(-0.18920\)
91.b1	91b3	\([0, 1, 1, -117, -1245]\)	\(-178643795968/524596891\)	\(-524596891\)	\([]\)	\(36\)	\(0.36010\)