Space of modular forms of level 18, weight 2, and trivial character

• Label: 18.2.a
• Level: $18$
• Weight: $2$
• Character orbit: 18.a
• Rep. character: $\chi_{18}(1,\cdot)$
• Character field: $\Q$
• Dimension: $0$
• Newform subspaces: $0$
• Sturm bound: $6$
• Trace bound: $0$

Defining parameters

Level:	\( N \)	\(=\)	\( 18 = 2 \cdot 3^{2} \)
Weight:	\( k \)	\(=\)	\( 2 \)
Character orbit:	\([\chi]\)	\(=\)	18.a (trivial)
Character field:			\(\Q\)
Newform subspaces:			\( 0 \)
Sturm bound:			\(6\)
Trace bound:			\(0\)

Dimensions

The following table gives the dimensions of various subspaces of \(M_{2}(\Gamma_0(18))\).

	Total	New	Old
Modular forms	7	0	7
Cusp forms	0	0	0
Eisenstein series	7	0	7

The following table gives the dimensions of the cuspidal new subspaces with specified eigenvalues for the Atkin-Lehner operators and the Fricke involution.

\(2\)	\(3\)	Fricke		Total				Cusp				Eisenstein
				All	New	Old		All	New	Old		All	New	Old
\(+\)	\(+\)	\(+\)		\(1\)	\(0\)	\(1\)		\(0\)	\(0\)	\(0\)		\(1\)	\(0\)	\(1\)
\(+\)	\(-\)	\(-\)		\(2\)	\(0\)	\(2\)		\(0\)	\(0\)	\(0\)		\(2\)	\(0\)	\(2\)
\(-\)	\(+\)	\(-\)		\(2\)	\(0\)	\(2\)		\(0\)	\(0\)	\(0\)		\(2\)	\(0\)	\(2\)
\(-\)	\(-\)	\(+\)		\(2\)	\(0\)	\(2\)		\(0\)	\(0\)	\(0\)		\(2\)	\(0\)	\(2\)
Plus space		\(+\)		\(3\)	\(0\)	\(3\)		\(0\)	\(0\)	\(0\)		\(3\)	\(0\)	\(3\)
Minus space		\(-\)		\(4\)	\(0\)	\(4\)		\(0\)	\(0\)	\(0\)		\(4\)	\(0\)	\(4\)