A chord sequence whose root rises in semitone steps, resolving typically to I in 1st inversion. biio is equivalent to VI7b9, so there is a turnaround feel to the first 3 chords, but instead of V the biiio chord appears. This can include the #5 (as diminished 7ths often do), which is the leading note, and the chord functions as a leading chord back to I (although it isn't the equivalent of V7b9).
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Easy Living