Plurals in Welsh

Fragment of a discussion from User talk:Lloffiwr

Sadly, I know nothing about Gettext.

Lloffiwr12:07, 4 April 2011
cy      nplurals=4; plural=(n == 1) ? 0 : ( (n == 2) ? 1 : ( (n != 8 && n != 11) ? 2 : 3 ) );
Nike13:19, 4 April 2011

Am I right in thinking that there is a rule for 0;1;8&11;everything else?

I believe that there is a very obscure exception for mutation with 8 and 11, which is used with three words only, two of which (sterling pound and hundred) will not appear as words anyway, and is very old-fashioned. The rule for 8 and 11 used to be in CLDR as well, but the Bedwyr Language Centre, at my request, negotiated with CLDR to replace it with the most important rules, for 0;1;2;3;6;everything else.

Lloffiwr16:01, 4 April 2011

Apparently, the CLDR has:

 Rule P:
   zero: n is 0
   one: n is 1
   two: n is 2
   few: n is 3
   many: n is 6

I'll try to update the Gettext rule to match

Nike16:12, 4 April 2011