Nexus 9 でビルド番号: N9F27M、

Factory Images for Nexus and Pixel Devices  |  Google Play services
https://developers.google.com/android/images#volantis
"volantis" for Nexus 9 (Wi-Fi)
7.1.1 (N9F27M, Oct 2017)
https://dl.google.com/dl/android/aosp/volantis-n9f27m-factory-a0d47736.zip
volantis-n9f27m-factory-a0d47736.zip (827,943,446 bytes)

または

Full OTA Images for Nexus and Pixel Devices  |  Google Play services
https://developers.google.com/android/ota#volantis
7.1.1 (N9F27M, Oct 2017)
https://dl.google.com/dl/android/aosp/volantis-ota-n9f27m-ad1aee0f.zip
volantis-ota-n9f27m-ad1aee0f.zip (817,456,682 bytes)

を使用している (または使用できる) 方にお願いです...
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