Rachael Stirling Rachael Stirling Rachael Atlanta Stirling (born 30 May 1977) is an English stage, film and television actress. She has been nominated twice for the Laurence Olivier Award for her stage work. She played Nancy Astley in the BBC drama "Tipping the Velvet", and Millie in the ITV series "The Bletchley Circle". She has also appeared in programmes such as "Lewis", and the long-running BBC One science fiction drama "Doctor Who". Stirling is the daughter of actress Diana Rigg and theatre producer Archibald Stirling. Her parents married in 1982 and divorced in 1990. Through her father, she has a long line
Stirling numbers of the second kind Stirling numbers of the second kind In mathematics, particularly in combinatorics, a Stirling number of the second kind (or Stirling partition number) is the number of ways to partition a set of "n" objects into "k" non-empty subsets and is denoted by formula_1 or formula_2. Stirling numbers of the second kind occur in the field of mathematics called combinatorics and the study of partitions. Stirling numbers of the second kind are one of two kinds of Stirling numbers, the other kind being called Stirling numbers of the first kind (or Stirling cycle numbers). Mutually inverse (finite or infinite) triangular matrices