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.

A295370 Number of permutations of [n] avoiding three consecutive terms in arithmetic progression.

Table of values

n a(n)
0 1
1 1
2 2
3 4
4 18
5 80
6 482
7 3280
8 26244
9 231148
10 2320130
11 25238348
12 302834694
13 3909539452
14 54761642704
15 816758411516
16 13076340876500
17 221396129723368
18 3985720881222850
19 75503196628737920
20 1510373288335622576
21 31634502738658957588
22 696162960370556156224
23 15978760340940405262668

List of values

[1, 1, 2, 4, 18, 80, 482, 3280, 26244, 231148, 2320130, 25238348, 302834694, 3909539452, 54761642704, 816758411516, 13076340876500, 221396129723368, 3985720881222850, 75503196628737920, 1510373288335622576, 31634502738658957588, 696162960370556156224, 15978760340940405262668]

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

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