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.

A005490 Number of partitions of [n] where the first k elements are marked (0 <= k <= n-1) and at least k blocks contain their own index.

Table of values

n a(n)
1 1
2 4
3 13
4 44
5 163
6 666
7 2985
8 14550
9 76497
10 430746
11 2582447
12 16403028
13 109918745
14 774289168
15 5715471605
16 44087879136
17 354521950931
18 2965359744446
19 25749723493073
20 231719153184018
21 2157494726318233
22 20753996174222510
23 205985762120971167
24 2106795754056142536

List of values

[1, 4, 13, 44, 163, 666, 2985, 14550, 76497, 430746, 2582447, 16403028, 109918745, 774289168, 5715471605, 44087879136, 354521950931, 2965359744446, 25749723493073, 231719153184018, 2157494726318233, 20753996174222510, 205985762120971167, 2106795754056142536]

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

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