Atlas › Modular forms › Weight 2 › Level 689 › 689.2.a › 689.2.a.g

Newform orbit 689.2.a.g

Trace form

The 18 newforms in this orbit are conjugate over $\mathbb{Q}$ ; the sum of their $q$ -expansions is

$18q + 2q^{2} + 5q^{3} + 30q^{4} + q^{5} - q^{6} + 3q^{7} + 6q^{8} + 27q^{9} + 9q^{10} + 3q^{11} + 19q^{12} - 18q^{13} + 5q^{14} + 17q^{15} + 54q^{16} - q^{17} - 11q^{18} + 3q^{20} + 6q^{21} + 19q^{22} + 16q^{23} + 7q^{24} + O(q^{25})$

Coefficient field

The coefficients $a_n$ generate a number field of degree 18. It is generated by the eigenvalue $\alpha$ of $T = T_{2} + 3T_{3}$ , whose minimal polynomial is

$x^{18} - 17x^{17} - 250x^{16} + 5391x^{15} + 19798x^{14} - 692301x^{13} - 141841x^{12} + 46847932x^{11} - 61375822x^{10} - 1826810696x^{9} + 3581022684x^{8} + 42342540288x^{7} - 87928170131x^{6} - 577299076167x^{5} + 1030196372610x^{4} + 4278007755245x^{3} - 5078192176312x^{2} - 13041963871671x + 6287148002125$

Atkin–Lehner signs

$p$	$w_p$
13	$+1$
53	$-1$

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 even 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	5	1	3	3	−18	−1	0	16	−3	42	4	−13	16	−5	18	−8	34	−2	46	−37	83	−24	10	−4

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

Provenance

Stored in the atlas: computed by Sagebrush's modular symbols engine in 0.237 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, 13, 53, 689]: [0, 1, 5, 64] (certified at ell = 2147483053)
T = [(2, 1), (3, 3)]; h of degree 53 = 1 x 53 (phi(ord eps) x dim S_k^new); 7 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(689, 2)[6]   # 689.2.a.g

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

cargo run --release -p sagebrush-web --example atlas -- 689:2 1000