XXXVIIXXXIX
XXXVIIXXXIX is a sequence of Roman numerals that, when interpreted literally, is highly unusual and does not conform to standard Roman numeral notation. The sequence begins with XXXVII, which represents 37 (XXX = 30, VII = 7). This is followed immediately by XXXIX, which represents 39 (XXX = 30, IX = 9). The juxtaposition of these two complete Roman numerals without any clear mathematical operation indicated is the primary source of its peculiarity.
In standard Roman numeral practice, values are generally additive (e.g., XII = 10 + 1 + 1 = 12) or