Atlas › Modular forms › Weight 2 › Level 806 › 806.2.a › 806.2.a.g

Newform orbit 806.2.a.g

Trace form

The 2 newforms in this orbit are conjugate over $\mathbb{Q}$ ; the sum of their $q$ -expansions is

$2q - 2q^{2} + 2q^{4} - 2q^{5} - 4q^{7} - 2q^{8} + 4q^{9} + 2q^{10} - 2q^{11} + 2q^{13} + 4q^{14} + 2q^{16} + 2q^{17} - 4q^{18} - 8q^{19} - 2q^{20} - 10q^{21} + 2q^{22} + 14q^{23} + O(q^{25})$

Coefficient field

The coefficients $a_n$ generate $\mathbb{Q}(\sqrt{5})$ . It is generated by the eigenvalue $\alpha$ of $T = T_{3} + 2T_{5} + 3T_{7} + 4T_{11} + 5T_{17} + 6T_{19} + 7T_{23} + 8T_{29}$ , whose minimal polynomial is

$x^{2} + 28x - 4009$

Atkin–Lehner signs

$p$	$w_p$
2	$+1$
13	$-1$
31	$-1$

For $p \parallel N$ every form in the orbit has $a_p = -p^{k/2-1} w_p$ . The Fricke sign is $w_N = +1$ , so the sign of the functional equation is $(-1)^{k/2} w_N = -1$ : each L-function in the orbit has odd analytic rank.

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
$\operatorname{tr} a_p$	−2	0	−2	−4	−2	2	2	−8	14	−8	2	−14	−10	−8	4	−6	14	−14	−14	16	12	−12	−16	2	0

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

Provenance

Stored in the atlas: computed by Sagebrush's modular symbols engine in 0.541 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, 13, 26, 31, 62, 403, 806]: [0, 1, 1, 5, 3, 10, 38, 116] (certified at ell = 2147482921)
T = [(3, 1), (5, 2), (7, 3), (11, 4), (17, 5), (19, 6), (23, 7), (29, 8)]; h of degree 29 = 1 x 29 (phi(ord eps) x dim S_k^new); 8 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(806, 2)[6]   # 806.2.a.g

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

cargo run --release -p sagebrush-web --example atlas -- 806:2 1000