Atlas › Modular forms › Weight 2 › Level 847 › 847.2.a › 847.2.a.i

Newform orbit 847.2.a.i

Trace form

The 3 newforms in this orbit are conjugate over $\mathbb{Q}$ ; the sum of their $q$ -expansions is

$3q - 2q^{2} - q^{3} + 8q^{4} + q^{5} - 12q^{6} - 3q^{7} - 6q^{8} + 4q^{9} + 4q^{10} + 2q^{12} - 8q^{13} + 2q^{14} - 5q^{15} + 10q^{16} - 8q^{17} + 18q^{18} - 14q^{20} + q^{21} + 7q^{23} - 20q^{24} + O(q^{25})$

Coefficient field

The coefficients $a_n$ generate a number field of degree 3. It is generated by the eigenvalue $\alpha$ of $T = T_{2} + 3T_{3} + 5T_{5} + 7T_{13}$ , whose minimal polynomial is

$x^{3} + 56x^{2} + 415x - 4850$

Atkin–Lehner signs

$p$	$w_p$
7	$+1$
11	— ( $11^2 \mid 847$ )

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
$\operatorname{tr} a_p$	−2	−1	1	−3	0	−8	−8	0	7	0	−13	−17	−16	−4	4	−10	1	16	−3	5	−16	−28	−8	−21	−11

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

Provenance

Stored in the atlas: computed by Sagebrush's modular symbols engine in 0.343 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, 7, 11, 77, 121, 847]: [0, 1, 2, 10, 12, 90] (certified at ell = 2147482921)
T = [(2, 1), (3, 3), (5, 5), (13, 7)]; h of degree 55 = 1 x 55 (phi(ord eps) x dim S_k^new); 12 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(847, 2)[8]   # 847.2.a.i

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

cargo run --release -p sagebrush-web --example atlas -- 847:2 1000