Texas Instruments TITANIUM TI-89 - Manual (Page 276)

Symbolic Manipulation 276
@n1 ... @n255 @n1 ... @n255 @n1 ... @n255 @n1 ... @n255
This notation indicates an “arbitrary integer”
that represents any integer.
When an arbitrary integer occurs multiple
times in the same session, each occurrence is
numbered consecutively. After it reaches 255,
arbitrary integer consecutive numbering
restarts at @n0. Use Clean Up
2:NewProb to
reset to @n1.
Note: For @ , press: 8 9
A solution is at every
integer multiple of
p .
Both @n and @n2
represent any
arbitrary integer, but
this notation identifies
separate arbitrary
integers.