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.

A356446 Number of permutations f of {1,...,n} with f(1) = 2 and f(2) = 1 such that the numbers f(k)*f(k+1) (0 < k < n) are distinct and Sum_{k=1..n-1} 1/(f(k)*f(k+1)) = 1.

Table of values

n a(n)
2 0
3 0
4 0
5 0
6 1
7 1
8 1
9 1
10 2
11 1
12 11
13 7
14 61
15 388
16 2933
17 2741

List of values

[0, 0, 0, 0, 1, 1, 1, 1, 2, 1, 11, 7, 61, 388, 2933, 2741]

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

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