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.

A095816 Number of permutations of 1..n with no three elements in correct or reverse order.

Table of values

n a(n)
0 1
1 1
2 2
3 4
4 18
5 92
6 570
7 4082
8 33292
9 304490
10 3086890
11 34357812
12 416526730
13 5463479106
14 77094352076
15 1164544912938
16 18749754351338
17 320544941916628
18 5799226664694602
19 110695180631374114
20 2223242026407894732
21 46868311165318977130
22 1034758905785710599402

List of values

[1, 1, 2, 4, 18, 92, 570, 4082, 33292, 304490, 3086890, 34357812, 416526730, 5463479106, 77094352076, 1164544912938, 18749754351338, 320544941916628, 5799226664694602, 110695180631374114, 2223242026407894732, 46868311165318977130, 1034758905785710599402]

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

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