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.

A207821 Number of permutations of [n] that either have a fixed point or a succession, but not both.

Table of values

n a(n)
0 0
1 1
2 0
3 5
4 12
5 69
6 370
7 2609
8 20552
9 183249
10 1817794
11 19867793
12 237126320
13 3068483277
14 42788761294
15 639619513669
16 10202914060472
17 172984071549421
18 3106257794721534
19 58892020126278457
20 1175554242034515780
21 24643158882899363129
22 541279064964716455230
23 12431122899361840993737
24 297944099946417376956220
25 7439329384072966947792437

List of values

[0, 1, 0, 5, 12, 69, 370, 2609, 20552, 183249, 1817794, 19867793, 237126320, 3068483277, 42788761294, 639619513669, 10202914060472, 172984071549421, 3106257794721534, 58892020126278457, 1175554242034515780, 24643158882899363129, 541279064964716455230, 12431122899361840993737, 297944099946417376956220, 7439329384072966947792437]

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

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