cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A136300 Numerator of ratio (the denominator being (n-1)!^2 = A001044(n-1)) giving the probability that the last of n persons drawing names randomly from a set of names draws their own, given that each person previously has drawn in succession and did not keep their own name. (Probability of derangements when allocated / rejected sequentially.)

Table of values

n a(n)
1 1
2 0
3 1
4 5
5 76
6 1624
7 52116
8 2298708
9 133929216
10 9961180416
11 921248743680
12 103715841415680
13 13967643016085760
14 2217449301162071040
15 409861043056032503040
16 87262626872384643052800
17 21202798521768886355558400
18 5831660090586059239329792000
19 1802587564536011525042697830400

List of values

[1, 0, 1, 5, 76, 1624, 52116, 2298708, 133929216, 9961180416, 921248743680, 103715841415680, 13967643016085760, 2217449301162071040, 409861043056032503040, 87262626872384643052800, 21202798521768886355558400, 5831660090586059239329792000, 1802587564536011525042697830400]

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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