It looks like the number of w-combinations from a set of c+w elements: C(c+w,w) = (c+w)!/(c+w-w)!w!

Yes, that's probably it.

I mean, that is definitely the derivation of the formula; and it is probably where I recognise it from. Still, there is an itch in the back of my brain that is associating it with something quite different?

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re^7: combinations of given string by BrowserUk
in thread combinations of given string by Anonymous Monk

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