want better option name for a conversion function

[Skaperen]

i have a function that converts ints to strings, given the int value, the sequence of digits to convert with, the minimum width of the result, the prefix to pad the result with if it is shorter than the minimum width. the name "digits" for the sequence of digits to convert with, just doesn't seem quite right to me. is there a better name i can use? the len() of this string will be the default base, and the maximum base if the caller specifies a base.