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.

A224541 Number of doubly-surjective functions f:[n]->[3].

Table of values

n a(n)
6 90
7 630
8 2940
9 11508
10 40950
11 137610
12 445896
13 1410552
14 4390386
15 13514046
16 41278068
17 125405532
18 379557198
19 1145747538
20 3452182656
21 10388002848
22 31230066186
23 93828607686
24 281775226860
25 845929656900
26 2539047258150
27 7619759016090
28 22864712861880
29 68605412870088

List of values

[90, 630, 2940, 11508, 40950, 137610, 445896, 1410552, 4390386, 13514046, 41278068, 125405532, 379557198, 1145747538, 3452182656, 10388002848, 31230066186, 93828607686, 281775226860, 845929656900, 2539047258150, 7619759016090, 22864712861880, 68605412870088]

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

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