A381352 Conductors admitting a normalized weight-2 eta-quotient newform.

11, 14, 15, 20, 24, 27, 32, 36, 48, 64, 80, 144

Offset: 1

Author

Dimitris Cardaris, May 11 2025

Keywords

• nonn
• fini
• full

Comments

By the modularity theorem, each Q-isogeny class of elliptic curves of conductor N corresponds to a unique normalized rational weight-2 newform on Gamma_0(N). This sequence (classified by Martin & Ono) lists exactly those 12 conductors N for which that newform at level N can be written as a single eta-quotient.

Examples

			a(1) = 11 since f(z) = q-2*q^2-q^3+2*q^4+ ... = eta^2(z)*eta^2(11*z) on Gamma_0(11)
		

Links

• Yves Martin and Ken Ono, Eta-Quotients and Elliptic Curves, Proc. Amer. Math. Soc. 125, No 11 (1997), 3169-3176.

Crossrefs

Cf. A005788, A060564, A110620.