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.

A289718 The order of the semigroup of orientation-preserving or reserving full transformations of n elements.

Table of values

n a(n)
1 1
2 4
3 27
4 180
5 1015
6 5028
7 23051
8 101272
9 434835
10 1843320
11 7753471
12 32440884
13 135195307
14 561615460
15 2326740315
16 9617256944
17 39671268187
18 163352387952
19 671559953015
20 2756930503420
21 11303415274179
22 46290177094172
23 189368906605747
24 773942488240920
25 3160265160762575
26 12893881856438128
27 52567364492251191
28 214163336821005012
29 871950728486358835
30 3547937446945462500

List of values

[1, 4, 27, 180, 1015, 5028, 23051, 101272, 434835, 1843320, 7753471, 32440884, 135195307, 561615460, 2326740315, 9617256944, 39671268187, 163352387952, 671559953015, 2756930503420, 11303415274179, 46290177094172, 189368906605747, 773942488240920, 3160265160762575, 12893881856438128, 52567364492251191, 214163336821005012, 871950728486358835, 3547937446945462500]

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

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