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.

A271791 Number of set partitions of [n] having exactly four pairs (m,m+1) such that m is in some block b and m+1 is in block b+1.

Table of values

n a(n)
4 0
5 1
6 15
7 129
8 891
9 5611
10 34213
11 208230
12 1285094
13 8108722
14 52540098
15 350375379
16 2407395908
17 17048774736
18 124435165429
19 935736058614
20 7246161094614
21 57749473020305
22 473358586652328
23 3987856784525223
24 34506189729577186
25 306454001139880689
26 2791593349164080381

List of values

[0, 1, 15, 129, 891, 5611, 34213, 208230, 1285094, 8108722, 52540098, 350375379, 2407395908, 17048774736, 124435165429, 935736058614, 7246161094614, 57749473020305, 473358586652328, 3987856784525223, 34506189729577186, 306454001139880689, 2791593349164080381]

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

Content is available under The OEIS End-User License Agreement.