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.

A375923 Number of permutations of size n which are both two-clumped and co-two-clumped.

Table of values

n a(n)
0 1
1 1
2 2
3 6
4 24
5 112
6 582
7 3272
8 19550
9 122628
10 800392
11 5400342
12 37475474
13 266412680
14 1934033968
15 14300538652
16 107471798112
17 819442325086
18 6329551390064
19 49465665347580
20 390692732060804
21 3115700976866356
22 25067250869113332
23 203317147838575616
24 1661425311693158000

List of values

[1, 1, 2, 6, 24, 112, 582, 3272, 19550, 122628, 800392, 5400342, 37475474, 266412680, 1934033968, 14300538652, 107471798112, 819442325086, 6329551390064, 49465665347580, 390692732060804, 3115700976866356, 25067250869113332, 203317147838575616, 1661425311693158000]

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

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