For even integers k≥ℓ≥4\documentclass[12pt]{minimal}
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\begin{document}$$k\ge \ell \ge 4$$\end{document}, we consider the modular forms Ek+Eℓ++Ek+ℓ+\documentclass[12pt]{minimal}
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\begin{document}$$E_k^+E_\ell ^++E_{k+\ell }^+$$\end{document} for the Fricke group Γ0+(2)\documentclass[12pt]{minimal}
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\begin{document}$$\Gamma _0^+(2)$$\end{document}, where Ek+\documentclass[12pt]{minimal}
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\begin{document}$$E_k^+$$\end{document} is the Eisenstein series of weight k for Γ0+(2)\documentclass[12pt]{minimal}
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\begin{document}$$\Gamma _0^+(2)$$\end{document}, and we prove that if 26630≤ℓ<k≤77ℓ\documentclass[12pt]{minimal}
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\begin{document}$$26630\le \ell < k \le 77\ell $$\end{document} or k=ℓ≥10\documentclass[12pt]{minimal}
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\begin{document}$$k=\ell \ge 10$$\end{document}, then all of their zeros in the fundamental domain F+\documentclass[12pt]{minimal}
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\begin{document}$$\mathfrak {F}^+$$\end{document} for Γ0+(2)\documentclass[12pt]{minimal}
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\begin{document}$$\Gamma _0^+(2)$$\end{document} lie on the arc boundary of F+\documentclass[12pt]{minimal}
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\begin{document}$$\mathfrak {F}^+$$\end{document}.