[seqfan] Re: A173279 and A173280

[Robert Munafo]

I really like that idea Richard.

It would help to disambiguate the common function names like "phi", "sigma"
and "pi", which usually mean A000010, A000203, and A000720 respectively, but
could often use clarification to amateurs or newcomers.

- Robert

On Mon, Feb 22, 2010 at 15:12, Richard Mathar <mathar at strw.leidenuniv.nl>wrote:

> In this case, repeating what's already known is superfluous. However,
> using a formula line to repeat the definition to hammer down the meaning
> of what's found in the %N line makes perfect sense. If strange acronyms
> like "usigma", "sopf" "guuglehupf" and the more standard "sigma", "tau"
> "factorial" words are used in the definition, I'd prefer to see them
> again as  a(n) = Axxx(...Ayyy(n)) repeated in the formula line to be
> convinced
> that the definition is sound proof. Here, for example "a(n)="
> in the definition is superfluous, because "a(n) is" is some sort of
> default in the definition. The formula could, of course, not stand without
> a(n).
>
> Here, this sort of repetition makes sense to verify that the exclamation
> mark in the definition is not an emphatic n but a factorial:
>
> %N A173317 5*n!-1.
> %F A173317 a(n) = 5*A000142(n)-1.
>
> --
 Robert Munafo  --  mrob.com