[Cfp-interest 1717] footnote about sufficient %a formatting precision

[Jim Thomas]

This is about footnote 296) in the C2X draft (N 2478). 

The anchor for the footnote is talking about the formatting precision which is denoted in the subclauses by P, to distinguish it from a type precision p. So it would seem the footnote should be talking about P instead of p. 

Then, could the sufficiency inequality be loosened to 16^(P-1) >= b^n? P is the number of digits to the right of the decimal point character, not the total number of digits, though the digit to the left of decimal point character might just be 1.

- Jim Thomas