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.

A152499 1/12 of the number of permutations of 3 indistinguishable copies of 1..n with exactly 2 local maxima.

Table of values

n a(n)
1 0
2 1
3 30
4 664
5 13632
6 274432
7 5497344
8 109987840
9 2199945216
10 43999756288
11 879998926848
12 17599995314176
13 351999979683840
14 7039999912443904
15 140799999624609792
16 2815999998397775872
17 56319999993188450304
18 1126399999971143188480
19 22527999999878130302976

List of values

[0, 1, 30, 664, 13632, 274432, 5497344, 109987840, 2199945216, 43999756288, 879998926848, 17599995314176, 351999979683840, 7039999912443904, 140799999624609792, 2815999998397775872, 56319999993188450304, 1126399999971143188480, 22527999999878130302976]

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

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