Cremona's table of elliptic curves

20 = 2² · 5

Field	Data	Notes
Atkin-Lehner	2- 5+	Signs for the Atkin-Lehner involutions
Conductor	20	Conductor
Count	4	Number of curves in isogeny class
Curves	20a1 20a2 20a3 20a4	Curves in isogeny class
deg	1	Modular degree for the optimal curve
Eigenvalues	2- -2 5+  2  0  2 -6 -4	Hecke eigenvalues for primes less than 20
L	0.47072919032652	L(r)(E,1)/r!
r	0	Rank of the group of rational points
Twists	80b 320c 180a 100a	Quadratic twists by: -4 8 -3 5

Hecke Eigenvalues for isogeny class 20a

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	+	2	0	2	-6	-4	6	6	-4	2	6	-10	-6	-6	12	2	2	-12	2	8	6	-6	2

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Quadratic twists for isogeny class 20a

-4	8	-3	5	-7	-11	13	17	-19	-23	29	-31	37	41	-43	-47	53	-59	61	-67	-71	73	-79
80b	320c	180a	100a	980g	2420e	3380i	5780e	7220c	10580m	16820b	19220b	27380d	33620a	36980a	44180g	56180d	69620b	74420d	89780f	100820a	106580d	124820b

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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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