^ Yep, that's correct, officially that's how much A ONE sold (in other words, according to Oricon's rankings).
But, of course, Oricon only tracks the numbers from when the album charts in the top 300, so we'll never know how much it truly sold after it stopped charting (just like any other release)... It's quite possible that it is very close to 55k by now, but "officially" it stopped at 52,816.
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