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.

A285918 Number of ordered set partitions of [n] into three blocks such that equal-sized blocks are ordered with increasing least elements.

Table of values

n a(n)
3 1
4 18
5 75
6 420
7 1218
8 4242
9 14563
10 42930
11 132528
12 432960
13 1250340
14 3814629
15 12073701
16 35074482
17 106044555
18 331913202
19 967193328
20 2917846758
21 9062084298
22 26507831559
23 79848170823
24 246771097680
25 723922691700
26 2178960263415
27 6709005218503
28 19728686792637

List of values

[1, 18, 75, 420, 1218, 4242, 14563, 42930, 132528, 432960, 1250340, 3814629, 12073701, 35074482, 106044555, 331913202, 967193328, 2917846758, 9062084298, 26507831559, 79848170823, 246771097680, 723922691700, 2178960263415, 6709005218503, 19728686792637]

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

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