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.

A152496 1/3 of the number of permutations of 2 indistinguishable copies of 1..n with exactly 4 local maxima.

Table of values

n a(n)
1 0
2 0
3 0
4 113
5 16565
6 1216902
7 65819156
8 3026987243
9 126794945523
10 5020186173560
11 191940972943658
12 7179017518306893
13 264789361664356313
14 9680016979445645738
15 351879352694331441600
16 12745281650338440074831
17 460591166578400672643359
18 16621008007245773574764028

List of values

[0, 0, 0, 113, 16565, 1216902, 65819156, 3026987243, 126794945523, 5020186173560, 191940972943658, 7179017518306893, 264789361664356313, 9680016979445645738, 351879352694331441600, 12745281650338440074831, 460591166578400672643359, 16621008007245773574764028]

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

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