A362260 - cp's OEIS frontend

A362260 Maximum over 0 <= k <= n/2 of the number of permutations of two symbols occurring k and n-2*k times, respectively, where a permutation and its reversal are counted only once.

n	a(n)
0	1
1	1
2	1
3	1
4	2
5	2
6	4
7	6
8	9
9	12
10	19
11	28
12	44
13	66
14	110
15	170
16	255
17	396
18	651
19	1001
20	1519
21	2520
22	4032
23	6216
24	9752
25	15912
26	25236
27	38760
28	63090
29	101850
30	160050
31	248710
32	408760
33	653752
34	1021735
35	1634776
36	2656511
37	4218786
38	6562556
39	10737090
40	17299646
41	27313650
42	43249115

[1, 1, 1, 1, 2, 2, 4, 6, 9, 12, 19, 28, 44, 66, 110, 170, 255, 396, 651, 1001, 1519, 2520, 4032, 6216, 9752, 15912, 25236, 38760, 63090, 101850, 160050, 248710, 408760, 653752, 1021735, 1634776, 2656511, 4218786, 6562556, 10737090, 17299646, 27313650, 43249115]

cp's OEIS Frontend

A362260 Maximum over 0 <= k <= n/2 of the number of permutations of two symbols occurring k and n-2*k times, respectively, where a permutation and its reversal are counted only once.

Table of values

List of values