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.

A280882 Number of set partitions of [n] into exactly four blocks where sizes of distinct blocks are coprime.

Table of values

n a(n)
4 1
5 10
6 20
7 245
8 56
9 2100
10 2640
11 36795
12 8140
13 542542
14 72436
15 3311945
16 6050240
17 91668080
18 2505120
19 1972220235
20 92327460
21 5331136090
22 6360277000
23 320219686633
24 29187262016
25 4567704520100
26 3125812500200
27 39433339579725
28 19033980625296
29 2173716576665550

List of values

[1, 10, 20, 245, 56, 2100, 2640, 36795, 8140, 542542, 72436, 3311945, 6050240, 91668080, 2505120, 1972220235, 92327460, 5331136090, 6360277000, 320219686633, 29187262016, 4567704520100, 3125812500200, 39433339579725, 19033980625296, 2173716576665550]

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

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