Cremona's table of elliptic curves

20640 = 2⁵ · 3 · 5 · 43

Field	Data	Notes
Atkin-Lehner	2+ 3+ 5+ 43-	Signs for the Atkin-Lehner involutions
Conductor	20640	Conductor
Count	4	Number of curves in isogeny class
Curves	20640a1 20640a2 20640a3 20640a4	Curves in isogeny class
deg	10240	Modular degree for the optimal curve
Eigenvalues	2+ 3+ 5+  0  4 -2  2 -4	Hecke eigenvalues for primes less than 20
L	1.0922844050688	L(r)(E,1)/r!
r	0	Rank of the group of rational points
Twists	20640t 41280bj 61920ca 103200ch	Quadratic twists by: -4 8 -3 5

Hecke Eigenvalues for isogeny class 20640a

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
+	+	+	0	4	-2	2	-4	-4	-6	-4	2	-6	-	4	6	-4	10	12	0	-14	4	-12	18	2

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Quadratic twists for isogeny class 20640a

-4	8	-3	5
20640t	41280bj	61920ca	103200ch

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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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