Term
| Stirling Numbers (1st Kind): Recursion Relation |
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Definition
| Number of permutations of n elements that consist of exactly k cycles. |
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Term
| Stirling Numbers (1st Kind): Recursion Relation |
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Definition
Number of k partitions on a n set.
S(n, k) = S(n-1, k-1) + k*S(n-1, k)
S(n,1) = S(n,n) = 1
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Term
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Definition
k cuts on n dimensions:
P(k,n) = P(k-1, n) + P(k-1, n-1) |
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Term
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Definition
For lists: order matters, repetition is permissible
k lists from an n set:
k^n w/ no repetition: n!/(n-k)! |
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Term
| n-multisets (Enumeration) |
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Definition
set with repetition:
(n+k-1)!/(n-1)!k! |
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Term
| P(An) Where set A consists of n items (How many?) |
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Definition
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Term
| |An x Bm| Where A, B consist of n,m elements (How many?) |
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Definition
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Term
| Map Ax(AxA) to (AxA)xA (how many?) |
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Definition
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