The number of partitions of size k of a set of n elements are known as Stirling numbers of the second kind, and satisfy the recursion:
  • S(0, 0) = 1
  • S(n, 0) = 0 if n > 0
  • S(n, 1) = S(n, n) = 1
  • S(n, k) = S(n-1, k-1) + kS(n-1, k)

The source is a cpan perl module; a google search will almost certainly discover which one; but that is irrelevant.

All I'm looking for is a tangible explanation of the above description.

Can any Monk put me in my place by transcribing the above description Into English?

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.
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In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to [Answered; thanks.] Can this be explained in layman's terms? by BrowserUk

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