Searching the PDF for how to fit the Timeline in the window, in FCP its Command + Z, searched for Timeline and Zoom, Timeline magnification.
To toggle zooming in/out to/from full-sequence view, press the \ key.
More info on default keyboard shortcuts in the Help doc: http://helpx.adobe.com/content/help/en/premiere-pro/using/default-keyb oard-shortcuts.html
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