Atlas › Modular forms › Weight 8 › Level 18 › 18.8.a › 18.8.a.b

Newform orbit 18.8.a.b

$q$ -expansion

$q + 8q^{2} + 64q^{4} + 210q^{5} + 1016q^{7} + 512q^{8} + 1680q^{10} - 1092q^{11} + 1382q^{13} + 8128q^{14} + 4096q^{16} - 14706q^{17} - 39940q^{19} + 13440q^{20} - 8736q^{22} - 68712q^{23} + O(q^{25})$

Coefficient field

The coefficients $a_n$ generate $\mathbb{Q}$ . The eigenvalue of $T = T_{5} + T_{7}$ is a root of

$x - 1226$

Atkin–Lehner signs

$p$	$w_p$
2	$-1$
3	— ( $3^2 \mid 18$ )

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

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
$\operatorname{tr} a_p$	8	0	210	1016	−1092	1382	−14706	−39940	−68712	102570	227552	160526	−10842	−630748	−472656	1494018	−2640660	827702	−126004	1414728	980282	−3566800	−5672892	11951190	8682146

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

Sato–Tate

The normalized $a_p / 2p^{7/2}$ for the primes $p < 1000$ not dividing 18, against the semicircle $\tfrac{2}{\pi}\sqrt{1 - x^2}$ :

Provenance

Stored in the atlas: computed by Sagebrush's modular symbols engine in 0.254 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 engine's checks

dim M^+ at levels [1, 2, 3, 6, 9, 18]: [1, 3, 3, 9, 8, 23] (certified at ell = 2147483647)
T = [(5, 1), (7, 1)]; h of degree 2 = 1 x 2 (phi(ord eps) x dim S_k^new); 1 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(18, 8)[1]   # 18.8.a.b

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

cargo run --release -p sagebrush-web --example atlas -- 18:8 1000