Cremona's table of elliptic curves

21808 = 2⁴ · 29 · 47

Field	Data	Notes
Atkin-Lehner	2+ 29- 47-	Signs for the Atkin-Lehner involutions
Class	21808b	Isogeny class
Conductor	21808	Conductor
∏ cp	2	Product of Tamagawa factors cp
deg	2240	Modular degree for the optimal curve
Δ	-348928 = -1 · 28 · 29 · 47	Discriminant
Eigenvalues	2+ -2  0 -1 -3  0  8  0	Hecke eigenvalues for primes up to 20
Equation	[0,1,0,12,-20]	[a1,a2,a3,a4,a6]
Generators	[2:4:1]	Generators of the group modulo torsion
j	686000/1363	j-invariant
L	2.8983768517132	L(r)(E,1)/r!
Ω	1.5813110219454	Real period
R	0.91644743238033	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	10904a1 87232n1	Quadratic twists by: -4 8

Hecke Eigenvalues for elliptic curve 21808b1

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
+	-2	0	-1	-3	0	8	0	-8	-	-5	-2	11	-5	-	11	11	-8	4	9	-11	6	-1	16	-6

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Quadratic twists for elliptic curve 21808b1

-4	8
10904a1	87232n1

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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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