Cremona's table of elliptic curves

Curve 21a6

21 = 3 · 7



Data for elliptic curve 21a6

Field Data Notes
Atkin-Lehner 3- 7+ Signs for the Atkin-Lehner involutions
Class 21a Isogeny class
Conductor 21 Conductor
∏ cp 2 Product of Tamagawa factors cp
Δ -17294403 = -1 · 3 · 78 Discriminant
Eigenvalues -1 3- -2 7+  4 -2 -6  4 Hecke eigenvalues for primes up to 20
Equation [1,0,0,-34,-217] [a1,a2,a3,a4,a6]
j -4354703137/17294403 j-invariant
L 0.45111540538849 L(r)(E,1)/r!
Ω 0.90223081077698 Real period
R 1 Regulator
r 0 Rank of the group of rational points
S 1 (Analytic) order of Ш
t 2 Number of elements in the torsion subgroup
Twists 336e6 1344a6 63a6 525b6 Quadratic twists by: -4 8 -3 5


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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