Atlas › Modular forms › Weight 2 › Level 260 › 260.2.a › 260.2.a.b

Newform orbit 260.2.a.b

Trace form

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

$3q + 2q^{3} + 3q^{5} - 2q^{7} + 11q^{9} + 3q^{13} + 2q^{15} + 2q^{17} + 8q^{19} - 8q^{21} - 10q^{23} + O(q^{25})$

Coefficient field

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

$x^{3} - 24x - 36$

Atkin–Lehner signs

$p$	$w_p$
2	— ( $2^2 \mid 260$ )
5	$-1$
13	$-1$

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
$\operatorname{tr} a_p$	0	2	3	−2	0	3	2	8	−10	10	−12	−2	−2	−2	−10	−18	−16	14	14	0	14	8	−6	−2	26

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

Provenance

Stored in the atlas: computed by Sagebrush's modular symbols engine in 0.1 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, 5, 10, 13, 20, 26, 52, 65, 130, 260]: [0, 1, 2, 1, 3, 1, 6, 5, 10, 8, 24, 48] (certified at ell = 2147483629)
T = [(3, 1), (7, 1)]; h of degree 4 = 1 x 4 (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(260, 2)[1]   # 260.2.a.b

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

cargo run --release -p sagebrush-web --example atlas -- 260:2 1000