A271872 - cp's OEIS frontend

A271872 Decimal expansion of the doubly infinite sum N_3 = Sum_{i,j,k = -inf..inf} (-1)^(i+j+k)/(i^2+j^2+k^2), a lattice constant analog of Madelung's constant (negated).

n	a(n)
1	2
2	5
3	1
4	9
5	3
6	5
7	6
8	1
9	5
10	2
11	0
12	8
13	9
14	4
15	4
16	5
17	3
18	1
19	3
20	3
21	4
22	2
23	7
24	1
25	1
26	7
27	2
28	7
29	3
30	2
31	9
32	4
33	3
34	7
35	9
36	1
37	2
38	1
39	1
40	6
41	4
42	9
43	9
44	1
45	3
46	6
47	7
48	5
49	1
50	7
51	3
52	2
53	5
54	7
55	7
56	5
57	0
58	0
59	6
60	6
61	0
62	7
63	8
64	5
65	6
66	7
67	7
68	4
69	3
70	9
71	0
72	1
73	2
74	6
75	9
76	1
77	8
78	7
79	2
80	7
81	7
82	4
83	0
84	9
85	6
86	4
87	2
88	8
89	0
90	2
91	1
92	0
93	1
94	6
95	2
96	3
97	7
98	3
99	0
100	3
101	1

[2, 5, 1, 9, 3, 5, 6, 1, 5, 2, 0, 8, 9, 4, 4, 5, 3, 1, 3, 3, 4, 2, 7, 1, 1, 7, 2, 7, 3, 2, 9, 4, 3, 7, 9, 1, 2, 1, 1, 6, 4, 9, 9, 1, 3, 6, 7, 5, 1, 7, 3, 2, 5, 7, 7, 5, 0, 0, 6, 6, 0, 7, 8, 5, 6, 7, 7, 4, 3, 9, 0, 1, 2, 6, 9, 1, 8, 7, 2, 7, 7, 4, 0, 9, 6, 4, 2, 8, 0, 2, 1, 0, 1, 6, 2, 3, 7, 3, 0, 3, 1]

cp's OEIS Frontend

A271872 Decimal expansion of the doubly infinite sum N_3 = Sum_{i,j,k = -inf..inf} (-1)^(i+j+k)/(i^2+j^2+k^2), a lattice constant analog of Madelung's constant (negated).

Table of values

List of values

n	a(n)
1	2
2	5
3	1
4	9
5	3
6	5
7	6
8	1
9	5
10	2
11	0
12	8
13	9
14	4
15	4
16	5
17	3
18	1
19	3
20	3
21	4
22	2
23	7
24	1
25	1
26	7
27	2
28	7
29	3
30	2
31	9
32	4
33	3
34	7
35	9
36	1
37	2
38	1
39	1
40	6
41	4
42	9
43	9
44	1
45	3
46	6
47	7
48	5
49	1
50	7
51	3
52	2
53	5
54	7
55	7
56	5
57	0
58	0
59	6
60	6
61	0
62	7
63	8
64	5
65	6
66	7
67	7
68	4
69	3
70	9
71	0
72	1
73	2
74	6
75	9
76	1
77	8
78	7
79	2
80	7
81	7
82	4
83	0
84	9
85	6
86	4
87	2
88	8
89	0
90	2
91	1
92	0
93	1
94	6
95	2
96	3
97	7
98	3
99	0
100	3
101	1

n	a(n)
1	2
2	5
3	1
4	9
5	3
6	5
7	6
8	1
9	5
10	2
11	0
12	8
13	9
14	4
15	4
16	5
17	3
18	1
19	3
20	3
21	4
22	2
23	7
24	1
25	1
26	7
27	2
28	7
29	3
30	2
31	9
32	4
33	3
34	7
35	9
36	1
37	2
38	1
39	1
40	6
41	4
42	9
43	9
44	1
45	3
46	6
47	7
48	5
49	1
50	7
51	3
52	2
53	5
54	7
55	7
56	5
57	0
58	0
59	6
60	6
61	0
62	7
63	8
64	5
65	6
66	7
67	7
68	4
69	3
70	9
71	0
72	1
73	2
74	6
75	9
76	1
77	8
78	7
79	2
80	7
81	7
82	4
83	0
84	9
85	6
86	4
87	2
88	8
89	0
90	2
91	1
92	0
93	1
94	6
95	2
96	3
97	7
98	3
99	0
100	3
101	1

n	a(n)
1	2
2	5
3	1
4	9
5	3
6	5
7	6
8	1
9	5
10	2
11	0
12	8
13	9
14	4
15	4
16	5
17	3
18	1
19	3
20	3
21	4
22	2
23	7
24	1
25	1
26	7
27	2
28	7
29	3
30	2
31	9
32	4
33	3
34	7
35	9
36	1
37	2
38	1
39	1
40	6
41	4
42	9
43	9
44	1
45	3
46	6
47	7
48	5
49	1
50	7
51	3
52	2
53	5
54	7
55	7
56	5
57	0
58	0
59	6
60	6
61	0
62	7
63	8
64	5
65	6
66	7
67	7
68	4
69	3
70	9
71	0
72	1
73	2
74	6
75	9
76	1
77	8
78	7
79	2
80	7
81	7
82	4
83	0
84	9
85	6
86	4
87	2
88	8
89	0
90	2
91	1
92	0
93	1
94	6
95	2
96	3
97	7
98	3
99	0
100	3
101	1