[Cfp-interest 2880] one third in double-double

[David Hough CFP]

Pursuant to our discussion of the double-double example, I think the
components of 1/3 are

dec quad 	0.333333333333333314829616256247390993
dec double	3.333333333333333148E-1
hex double 	.AAAA AAAA AAAA A8H-1

dec quad	1.85037170770859423243444449316200398E-0017
dec double 	1.850371707708594131E-17
hex double	.AAAA AAAA AAAA A8H-55

If I understand the C hex representation which I haven't used myself, 
it would be

0x0.AAAAAAAAAAAAA8p-1
0x0.AAAAAAAAAAAAA8p-55

And the representations for two thirds would be

0x0.AAAAAAAAAAAAA8p0
0x0.AAAAAAAAAAAAA8p-54

Very convenient.