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.

A260785 Leading diagonal of triangle in A259689: a(n)= number of permutations without overlaps that generate exactly 2 permutations without overlaps in a(n+1).

Table of values

n a(n)
2 1
3 2
4 2
5 6
6 10
7 32
8 68
9 220
10 528
11 1724
12 4460
13 14664
14 39908
15 131944
16 372448
17 1237016
18 3589384
19 11967140
20 35479312
21 118675768
22 357957984
23 1200724776
24 3673173656
25 12351611656
26 38232022416

List of values

[1, 2, 2, 6, 10, 32, 68, 220, 528, 1724, 4460, 14664, 39908, 131944, 372448, 1237016, 3589384, 11967140, 35479312, 118675768, 357957984, 1200724776, 3673173656, 12351611656, 38232022416]

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

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