Elliptic curves over $\Q$ of conductor 21

Conductor	j-invariant	Rank	Torsion order	Torsion structure
Analytic order of Ш	$p$ div |Ш|	Maximal primes	Nonmax $p$	Bad $p$
Number of integral points	Regulator	CM	CM discriminant	Semistable
Curves per isogeny class	Cyclic isogeny degree	Isogeny class size	Isogeny class degree	Potential good reduction

Results (6 matches)

 

Curve		Isogeny class
LMFDB label	Cremona label	LMFDB label	Cremona label	Weierstrass coefficients	Rank	Torsion structure
21.a1	21a5	21.a	21a	$[1, 0, 0, -784, -8515]$	$0$	$[2]$
21.a2	21a2	21.a	21a	$[1, 0, 0, -49, -136]$	$0$	$[2, 2]$
21.a3	21a3	21.a	21a	$[1, 0, 0, -39, 90]$	$0$	$[8]$
21.a4	21a6	21.a	21a	$[1, 0, 0, -34, -217]$	$0$	$[2]$
21.a5	21a1	21.a	21a	$[1, 0, 0, -4, -1]$	$0$	$[2, 4]$
21.a6	21a4	21.a	21a	$[1, 0, 0, 1, 0]$	$0$	$[4]$