A319662 - cp's OEIS frontend

A319662 2-rank of the class group of Q(sqrt(-k)), k squarefree.

n	a(n)
1	0
2	0
3	0
4	1
5	1
6	0
7	1
8	0
9	1
10	1
11	1
12	1
13	0
14	2
15	1
16	0
17	1
18	1
19	2
20	0
21	2
22	1
23	1
24	1
25	1
26	1
27	1
28	2
29	0
30	1
31	0
32	1
33	1
34	1
35	2
36	1
37	0
38	1
39	1
40	2
41	2
42	0
43	2
44	2
45	0
46	1
47	1
48	2
49	2
50	0
51	1
52	0
53	2
54	1
55	1
56	1
57	1
58	2
59	1
60	1
61	1
62	1
63	2
64	0
65	3
66	1
67	0
68	1
69	2
70	1
71	1
72	2
73	1
74	1
75	1
76	1
77	1
78	0
79	2
80	2
81	0
82	2
83	1
84	1
85	2
86	0
87	2

[0, 0, 0, 1, 1, 0, 1, 0, 1, 1, 1, 1, 0, 2, 1, 0, 1, 1, 2, 0, 2, 1, 1, 1, 1, 1, 1, 2, 0, 1, 0, 1, 1, 1, 2, 1, 0, 1, 1, 2, 2, 0, 2, 2, 0, 1, 1, 2, 2, 0, 1, 0, 2, 1, 1, 1, 1, 2, 1, 1, 1, 1, 2, 0, 3, 1, 0, 1, 2, 1, 1, 2, 1, 1, 1, 1, 1, 0, 2, 2, 0, 2, 1, 1, 2, 0, 2]

cp's OEIS Frontend

A319662 2-rank of the class group of Q(sqrt(-k)), k squarefree.

Table of values

List of values

n	a(n)
1	0
2	0
3	0
4	1
5	1
6	0
7	1
8	0
9	1
10	1
11	1
12	1
13	0
14	2
15	1
16	0
17	1
18	1
19	2
20	0
21	2
22	1
23	1
24	1
25	1
26	1
27	1
28	2
29	0
30	1
31	0
32	1
33	1
34	1
35	2
36	1
37	0
38	1
39	1
40	2
41	2
42	0
43	2
44	2
45	0
46	1
47	1
48	2
49	2
50	0
51	1
52	0
53	2
54	1
55	1
56	1
57	1
58	2
59	1
60	1
61	1
62	1
63	2
64	0
65	3
66	1
67	0
68	1
69	2
70	1
71	1
72	2
73	1
74	1
75	1
76	1
77	1
78	0
79	2
80	2
81	0
82	2
83	1
84	1
85	2
86	0
87	2

n	a(n)
1	0
2	0
3	0
4	1
5	1
6	0
7	1
8	0
9	1
10	1
11	1
12	1
13	0
14	2
15	1
16	0
17	1
18	1
19	2
20	0
21	2
22	1
23	1
24	1
25	1
26	1
27	1
28	2
29	0
30	1
31	0
32	1
33	1
34	1
35	2
36	1
37	0
38	1
39	1
40	2
41	2
42	0
43	2
44	2
45	0
46	1
47	1
48	2
49	2
50	0
51	1
52	0
53	2
54	1
55	1
56	1
57	1
58	2
59	1
60	1
61	1
62	1
63	2
64	0
65	3
66	1
67	0
68	1
69	2
70	1
71	1
72	2
73	1
74	1
75	1
76	1
77	1
78	0
79	2
80	2
81	0
82	2
83	1
84	1
85	2
86	0
87	2

n	a(n)
1	0
2	0
3	0
4	1
5	1
6	0
7	1
8	0
9	1
10	1
11	1
12	1
13	0
14	2
15	1
16	0
17	1
18	1
19	2
20	0
21	2
22	1
23	1
24	1
25	1
26	1
27	1
28	2
29	0
30	1
31	0
32	1
33	1
34	1
35	2
36	1
37	0
38	1
39	1
40	2
41	2
42	0
43	2
44	2
45	0
46	1
47	1
48	2
49	2
50	0
51	1
52	0
53	2
54	1
55	1
56	1
57	1
58	2
59	1
60	1
61	1
62	1
63	2
64	0
65	3
66	1
67	0
68	1
69	2
70	1
71	1
72	2
73	1
74	1
75	1
76	1
77	1
78	0
79	2
80	2
81	0
82	2
83	1
84	1
85	2
86	0
87	2