Is the proper term for a base-three number system “trinary” or “ternary”? Would a base-four system be “quaternary”? I know that base-two is “binary”, base-eight is “octal”, base-ten is “decimal” and base-sixteen is “hexadecimal” but what would the others between base-two and base-sixteen be? I have some educated guesses on a few: Base-nine - “nonal”? Base-eleven - “unadecimal”? Base-twelve - “duodecimal”?
Oh and there is actually such a thing as “unary” (e.g. the “-” in “-16” is a unary mathematical operator) but I don’t think you could actually have a unary or base-one number system, for obvious reasons.
Main Entry: 2tertiary
Function: adjective
Etymology: Latin tertiarius of or containing a third, from tertius third
Date: circa 1656
1 a : of third rank, importance, or value b chiefly British : of, relating to, or being higher education c : of, relating to, or constituting the third strongest of the three or four degrees of stress recognized by most linguists (as the stress of the third syllable of basketball team)
3 a : involving or resulting from the substitution of three atoms or groups <a tertiary salt> <tertiary amine> b : being or containing a carbon atom having bonds to three other carbon atoms <an acid containing a tertiary carbon> <tertiary alcohols>
4 : occurring in or being a third stage: as a : being or relating to the recovery of oil and gas from old wells by means of the underground application of heat and chemicals b : being or relating to the purification of wastewater by removal of fine particles, nitrates, and phosphates
The accepted term for a base three number system is “ternary”. Bases other than 2, 4, 8, 10, and 16 don’t show up often enough to warrant special names (at least in my experience); base k is usually just referred to as “base k”.
There is a unary number system, suitable only for representing integers. 1 is represented as 1, 2 is represented as 11, and so on and so forth. It does require a different symbol for zero, though. Clearly this is not the same as a base 1 number system.