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.

A227914 Length of longest chain of nonempty proper subsemigroups of the symmetric inverse monoid.

Table of values

n a(n)
1 1
2 6
3 25
4 116
5 722
6 5956
7 59243
8 667500
9 8296060
10 112406158
11 1648441865
12 26016230581
13 439698829588
14 7923291500266
15 151636272041063
16 3071397457222772
17 65637064987470128
18 1475783903907314842
19 34822081020977308581
20 860290584362463964031
21 22206678791494395506940
22 597775158911764084886982
23 16751152450234618859184419
24 487867395080603697285978385
25 14745549219503008426659528806

List of values

[1, 6, 25, 116, 722, 5956, 59243, 667500, 8296060, 112406158, 1648441865, 26016230581, 439698829588, 7923291500266, 151636272041063, 3071397457222772, 65637064987470128, 1475783903907314842, 34822081020977308581, 860290584362463964031, 22206678791494395506940, 597775158911764084886982, 16751152450234618859184419, 487867395080603697285978385, 14745549219503008426659528806]

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

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