the ti-51-iii is the same as the ti-55 and appeared for the
european market.
like the ti-57 the display is only 8 digits led,
but 11 figures are used internally. its also programmable, but true programming
facilities are lacking. it has a 32 step memory, but there are no
conditional branches and only one non-conditional branch back to the
program start (ie step 0).

there are a good set of scientific and statistical functions available
and also some useful unit conversions. 2d stats on offer was somewhat rare
at this time giving linear regression and the correlation coefficient.

## example program: nim

here is an implementation of nim. you and the machine take turns to
remove either 1, 2, or 3 matches from a pile. the player to take the last
match *loses*.