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.

A159716 Number of permutations of 2 indistinguishable copies of 1..n arranged in a circle with exactly 2 local maxima.

Table of values

n a(n)
2 2
3 66
4 1168
5 16220
6 202416
7 2395540
8 27517568
9 310123764
10 3447919120
11 37934904788
12 413863668480
13 4483624403284
14 48285543009872
15 517346347249140
16 5518365322864384
17 58632646191319220
18 620816303380261392
19 6553061146974071956
20 68979591578665208960
21 724285713430953995412

List of values

[2, 66, 1168, 16220, 202416, 2395540, 27517568, 310123764, 3447919120, 37934904788, 413863668480, 4483624403284, 48285543009872, 517346347249140, 5518365322864384, 58632646191319220, 620816303380261392, 6553061146974071956, 68979591578665208960, 724285713430953995412]

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

Content is available under The OEIS End-User License Agreement.