wanted software feature

– for gmail to have ‘read within the last 24 hours’ as one of its categories. If I read an email message on my cell phone, the message loses its ‘unread’ status, but I might want to remember to view it again when I’m at my computer. If this category exists, then I can simply routinely check it every time I check my email and catch an already-read email message that I wanted to look at again but might (sooner or later WILL) forget to do so because without this category it will have slipped over the horizon, being subject to the ‘out of sight, out of mind’ syndrome.
[user friendliness]
[Information Technology (IT)]
[user interface]

sum of exponents: Omega

The number of prime factors of a given number, counting their multiplicity, is given by the upper case prime omega function, i.e., Ω. For example, Ω(12) = 3. Note that Ω(n) is synonymous with the sum of the exponents in the canonical prime factorization of n.
(The lower-case omega function gives the number of prime factors, IGNORING multiplicity.)
Here is the link to the Wikipedia article on this.
[Number Theory]
[counting functions]