A015818 - cp's OEIS frontend

A015818 Number of solutions of +- 1 +- 2 +- ... +- (n-1) +- n = 0 in which the partial sums +- 1 +- ... +- k (1<=k<=n) are all distinct.

n	a(n)
0	1
1	0
2	0
3	2
4	2
5	0
6	0
7	2
8	2
9	0
10	0
11	10
12	14
13	0
14	0
15	36
16	40
17	0
18	0
19	134
20	258
21	0
22	0
23	702
24	1040
25	0
26	0
27	4170
28	5996
29	0
30	0
31	23642
32	36616
33	0
34	0
35	140500
36	217002
37	0
38	0
39	852132
40	1374692
41	0
42	0
43	5411800
44	8852230
45	0
46	0
47	35764246
48	56370054
49	0
50	0
51	232969442
52	376479130
53	0
54	0
55	1555855594
56	2534308444

[1, 0, 0, 2, 2, 0, 0, 2, 2, 0, 0, 10, 14, 0, 0, 36, 40, 0, 0, 134, 258, 0, 0, 702, 1040, 0, 0, 4170, 5996, 0, 0, 23642, 36616, 0, 0, 140500, 217002, 0, 0, 852132, 1374692, 0, 0, 5411800, 8852230, 0, 0, 35764246, 56370054, 0, 0, 232969442, 376479130, 0, 0, 1555855594, 2534308444]

cp's OEIS Frontend

A015818 Number of solutions of +- 1 +- 2 +- ... +- (n-1) +- n = 0 in which the partial sums +- 1 +- ... +- k (1<=k<=n) are all distinct.

Table of values

List of values