Atlas › Modular forms › Weight 2 › Level 392 › 392.2.a › 392.2.a.c

Newform orbit 392.2.a.c

$q$ -expansion

$q - q^{3} - q^{5} - 2q^{9} + 3q^{11} - 6q^{13} + q^{15} - 5q^{17} + q^{19} - 7q^{23} + O(q^{25})$

Coefficient field

The coefficients $a_n$ generate $\mathbb{Q}$ . The eigenvalue of $T = T_{3} + 2T_{5} + 3T_{11} + 4T_{13} + 5T_{17} + 6T_{19} + 7T_{23} + 8T_{29}$ is a root of

$x + 70$

Atkin–Lehner signs

$p$	$w_p$
2	— ( $2^2 \mid 392$ )
7	— ( $7^2 \mid 392$ )

For $p \parallel N$ every form in the orbit has $a_p = -p^{k/2-1} w_p$ .

Elliptic curve

By modularity this newform is the one attached to the isogeny class 392.c (Cremona's 392c). Its optimal curve 392c1 is

$y^2 = x^3 - x^2 - 16x + 29$

of rank 1 with torsion of order 1. Its $a_p$ , computed by Sagebrush's point-counting engine, equal the newform's for every prime $p < 1000$ .

Traces of Hecke eigenvalues

$p$	2	3	5	7	11	13	17	19	23	29	31	37	41	43	47	53	59	61	67	71	73	79	83	89	97
$\operatorname{tr} a_p$	0	−1	−1	0	3	−6	−5	1	−7	2	−5	3	−2	−4	5	−1	15	−5	−9	0	7	1	12	7	−2

$\operatorname{tr} a_n$ for every $n \le 1000$ is in the JSON.

Sato–Tate

The normalized $a_p / 2p^{1/2}$ for the primes $p < 1000$ not dividing 392, against the semicircle $\tfrac{2}{\pi}\sqrt{1 - x^2}$ :

Provenance

Stored in the atlas: computed by Sagebrush's modular symbols engine in 0.413 s (one thread) and proven: the dimensions are certified, and the characteristic polynomial of $T$ over $\mathbb{Z}$ is reconstructed by CRT past a rigorous coefficient bound. The label, dimension and $\operatorname{tr} a_p$ for every $p < 1000$ equal LMFDB's.

The engine's checks

dim M^+ at levels [1, 2, 4, 7, 8, 14, 28, 49, 56, 98, 196, 392]: [0, 1, 2, 1, 3, 4, 7, 5, 12, 16, 31, 60] (certified at ell = 2147483647)
T = [(3, 1), (5, 2), (11, 3), (13, 4), (17, 5), (19, 6), (23, 7), (29, 8)]; h of degree 10 = 1 x 10 (phi(ord eps) x dim S_k^new); 3 primes, 0 rejected

Open in the notebook · JSON · stored data

Recompute it yourself

In Sage mode at sagebrush.space (or npx sagebrush --sage):

newform_orbits(392, 2)[2]   # 392.2.a.c

With the Rust engine (source), in engine/:

cargo run --release -p sagebrush-web --example atlas -- 392:2 1000