Cremona's table of elliptic curves

21805 = 5 · 7² · 89

Field	Data	Notes
Atkin-Lehner	5- 7- 89+	Signs for the Atkin-Lehner involutions
Class	21805d	Isogeny class
Conductor	21805	Conductor
∏ cp	1	Product of Tamagawa factors cp
deg	1536	Modular degree for the optimal curve
Δ	21805 = 5 · 72 · 89	Discriminant
Eigenvalues	-1  1 5- 7-  1  1  0 -6	Hecke eigenvalues for primes up to 20
Equation	[1,0,0,-15,20]	[a1,a2,a3,a4,a6]
Generators	[1:2:1]	Generators of the group modulo torsion
j	7649089/445	j-invariant
L	4.0677170813393	L(r)(E,1)/r!
Ω	3.7601756076001	Real period
R	1.0817891252519	Regulator
r	1	Rank of the group of rational points
S	1	(Analytic) order of Ш
t	1	Number of elements in the torsion subgroup
Twists	109025e1 21805b1	Quadratic twists by: 5 -7

Hecke Eigenvalues for elliptic curve 21805d1

a2	a3	a5	a7	a11	a13	a17	a19	a23	a29	a31	a37	a41	a43	a47	a53	a59	a61	a67	a71	a73	a79	a83	a89	a97
-1	1	-	-	1	1	0	-6	8	0	10	7	-12	0	8	-12	-12	-12	-2	15	-12	3	-5	+	0

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Quadratic twists for elliptic curve 21805d1

5	-7
109025e1	21805b1

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Data from Elliptic Curve Data by J. E. Cremona.
Design inspired by The Modular Forms Explorer by William Stein.

Part of Computational Number Theory
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