A137725 - cp's OEIS frontend

A137725 Number of sequences of length n with elements {-2,-1,+1,+2}, such that the sum of elements of the whole sequence but of no proper subsequence equals 0 modulo n. For n>=4, the number of Hamiltonian (directed) circuits on the circulant graph C_n(1,2).

n	a(n)
1	4
2	4
3	16
4	18
5	24
6	32
7	46
8	58
9	82
10	112
11	158
12	220
13	316
14	450
15	650
16	938
17	1364
18	1982
19	2892
20	4220
21	6170
22	9022
23	13206
24	19332
25	28314
26	41472
27	60760
28	89022
29	130446
30	191150
31	280120
32	410506
33	601600
34	881656
35	1292102
36	1893634
37	2775226
38	4067256
39	5960822
40	8735972
41	12803156
42	18763898
43	27499794
44	40302866
45	59066684

[4, 4, 16, 18, 24, 32, 46, 58, 82, 112, 158, 220, 316, 450, 650, 938, 1364, 1982, 2892, 4220, 6170, 9022, 13206, 19332, 28314, 41472, 60760, 89022, 130446, 191150, 280120, 410506, 601600, 881656, 1292102, 1893634, 2775226, 4067256, 5960822, 8735972, 12803156, 18763898, 27499794, 40302866, 59066684]

cp's OEIS Frontend

A137725 Number of sequences of length n with elements {-2,-1,+1,+2}, such that the sum of elements of the whole sequence but of no proper subsequence equals 0 modulo n. For n>=4, the number of Hamiltonian (directed) circuits on the circulant graph C_n(1,2).

Table of values

List of values