謎題/算術謎題/對數謎題/對數謎題 1 解答

謎題 | 算術謎題 | 對數謎題 | 對數謎題 1 解答

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${777 \over 121}:{\operatorname {log} _{\sqrt {\sqrt {\sqrt {\sqrt {\sqrt {\sqrt {\sqrt {7}}}}}}}}7}-7$