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.

A333631 Number of permutations of {1..n} with three consecutive terms in arithmetic progression.

Table of values

n a(n)
0 0
1 0
2 0
3 2
4 6
5 40
6 238
7 1760
8 14076
9 131732
10 1308670
11 14678452
12 176166906
13 2317481348
14 32416648496
15 490915956484
16 7846449011500
17 134291298372632
18 2416652824505150
19 46141903780094080
20 922528719841017424
21 19456439433050482412
22 427837767407051523776
23 9873256397944571377332

List of values

[0, 0, 0, 2, 6, 40, 238, 1760, 14076, 131732, 1308670, 14678452, 176166906, 2317481348, 32416648496, 490915956484, 7846449011500, 134291298372632, 2416652824505150, 46141903780094080, 922528719841017424, 19456439433050482412, 427837767407051523776, 9873256397944571377332]

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

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