perils of style sheets

[Arnold Zwicky]

from the New York Times science section today, 4/10/01 (p. D5 in my
west coast edition), explanation of a mathematical puzzle:

  As it turns out, this requirement can be perfectly met only
  when the number of players is one less than a power of two
  (three, seven, 15 and so on.)  [punctuation as in original;
  don't blame me]

i went along with "one less than a power of two", though i would have
written "a power of 2" (the *number* 2).  but then i came to "three,
seven, 15", which struck me as over the line.  maybe it's just my
previous life as a mathematician, but references to numbers should
be consistently by numerals, *especially* when they appear in
combination.

the style sheets tell you that number words up to some limit should be
written out, those over that limit written in decimal notation (the
style sheets differ as to what that limit is): "robin thought that
there were seven people coming to dinner, but in fact 14 people turned
up."  such rules are compromises between different motivations
(ordinary spellings vs. brevity), and the results are not always
entirely felicitous (why does no one recommend parallelism, or even
tolerance of alternatives?), but they make some sense.  translating
mathematical number symbols into words in some specific language does
not.

not: "the square roots of one are minus one and plus one; the square
roots of 49 are minus seven and plus seven; the square roots of 169
are -13 and +13."  but: "the square roots of 1 are -1 and +1", etc.
not: "three and seven are one less than a power of two; three and 15
are one less than a power of two; ten and 120 are one less than a
power of 11."  but: "3 and 7 are one [or perhaps 1] less than a power
of 2", etc.

grumble grumble.

arnold (zwicky at csli.stanford.edu)