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.

A152497 1/3 of the number of permutations of 2 indistinguishable copies of 1..n with exactly 5 local maxima.

Table of values

n a(n)
1 0
2 0
3 0
4 0
5 2464
6 744881
7 104768981
8 10276536243
9 822955247485
10 58200440129470
11 3799361321633144
12 235172542192199514
13 14040457016024386686
14 817688213483194898191
15 46806533018464413823463
16 2647280824791216788157413
17 148469293685889945755890443
18 8277727866556696292321356900

List of values

[0, 0, 0, 0, 2464, 744881, 104768981, 10276536243, 822955247485, 58200440129470, 3799361321633144, 235172542192199514, 14040457016024386686, 817688213483194898191, 46806533018464413823463, 2647280824791216788157413, 148469293685889945755890443, 8277727866556696292321356900]

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

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