Rimski brojevi veci od 3999

Rules regarding Roman numerals often state that a symbol representing 10^x may not precede any symbol larger than 10^x+1. For example, C cannot be preceded by I or V, only by X (or, of course, by a symbol representing a value larger than C). Thus, one should represent the number "ninety-nine" as XCIX, not as the "shortcut" IC. However, these rules are not universally followed.

This 'problem' manifested in questions as to why 1999 was not written simply IMM or MIM.

Zidar:
Kako se rimskim brojevima pise broj veci ili jednak od 4000?
3999 bi bilo valjda MMMXCMIX jer MMM = 3000, XC = 90, XCM = 990, XCMIX=999

Kako dalje? 4000 ne moze da bude MMMM jer ni 4 nije IIII nego IV.

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