A128137 - cp's OEIS frontend

A128137 A002260 * A128132.

n	a(n)
1	1
2	-1
3	4
4	-1
5	1
6	9
7	-1
8	1
9	5
10	16
11	-1
12	1
13	5
14	11
15	25
16	-1
17	1
18	5
19	11
20	19
21	36
22	-1
23	1
24	5
25	11
26	19
27	29
28	49
29	-1
30	1
31	5
32	11
33	19
34	29
35	41
36	64
37	-1
38	1
39	5
40	11
41	19
42	29
43	41
44	55
45	81
46	-1
47	1
48	5
49	11
50	19
51	29
52	41
53	55
54	71
55	100

[1, -1, 4, -1, 1, 9, -1, 1, 5, 16, -1, 1, 5, 11, 25, -1, 1, 5, 11, 19, 36, -1, 1, 5, 11, 19, 29, 49, -1, 1, 5, 11, 19, 29, 41, 64, -1, 1, 5, 11, 19, 29, 41, 55, 81, -1, 1, 5, 11, 19, 29, 41, 55, 71, 100]

cp's OEIS Frontend

A128137 A002260 * A128132.

Table of values

List of values

n	a(n)
1	1
2	-1
3	4
4	-1
5	1
6	9
7	-1
8	1
9	5
10	16
11	-1
12	1
13	5
14	11
15	25
16	-1
17	1
18	5
19	11
20	19
21	36
22	-1
23	1
24	5
25	11
26	19
27	29
28	49
29	-1
30	1
31	5
32	11
33	19
34	29
35	41
36	64
37	-1
38	1
39	5
40	11
41	19
42	29
43	41
44	55
45	81
46	-1
47	1
48	5
49	11
50	19
51	29
52	41
53	55
54	71
55	100

n	a(n)
1	1
2	-1
3	4
4	-1
5	1
6	9
7	-1
8	1
9	5
10	16
11	-1
12	1
13	5
14	11
15	25
16	-1
17	1
18	5
19	11
20	19
21	36
22	-1
23	1
24	5
25	11
26	19
27	29
28	49
29	-1
30	1
31	5
32	11
33	19
34	29
35	41
36	64
37	-1
38	1
39	5
40	11
41	19
42	29
43	41
44	55
45	81
46	-1
47	1
48	5
49	11
50	19
51	29
52	41
53	55
54	71
55	100

n	a(n)
1	1
2	-1
3	4
4	-1
5	1
6	9
7	-1
8	1
9	5
10	16
11	-1
12	1
13	5
14	11
15	25
16	-1
17	1
18	5
19	11
20	19
21	36
22	-1
23	1
24	5
25	11
26	19
27	29
28	49
29	-1
30	1
31	5
32	11
33	19
34	29
35	41
36	64
37	-1
38	1
39	5
40	11
41	19
42	29
43	41
44	55
45	81
46	-1
47	1
48	5
49	11
50	19
51	29
52	41
53	55
54	71
55	100