[Info-vax] disk sizes

[Phillip Helbig---undress to reply]

Standard hard-disk sizes are 1.07 GB, 2.1, 4.3 (or sometimes the more
precise 4.29---one rarely sees the more precise 2.15).  8.6 (8.59) is
also relatively common.  This is clear, since 1024^3=1073741824 and then
one has 2, 4 or 8 times this.  So far, so good.  After that, sizes tend
to be 9.1, 18 (18.2---though 17 (roughly twice 8.6) also exists), 36
(36.4), 73 (72.8) and 146.  These are also powers of two times the new 
basic size, but where does the 9.1 basic size come from?