A242742 - cp's OEIS frontend

A242742 Let k be the n-th composite number: then a(n) is the smallest base b such that b^(k-1) == 1 (mod k).

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

[5, 7, 9, 8, 11, 13, 15, 4, 17, 19, 21, 8, 23, 25, 7, 27, 26, 9, 31, 33, 10, 35, 6, 37, 39, 14, 41, 43, 45, 8, 47, 49, 18, 51, 16, 9, 55, 21, 57, 20, 59, 61, 63, 8, 65, 8, 25, 69, 22, 11, 73, 75, 26, 45, 34, 79, 81, 80, 83, 85, 4, 87, 28, 89, 91, 3, 93, 32, 95]

cp's OEIS Frontend

A242742 Let k be the n-th composite number: then a(n) is the smallest base b such that b^(k-1) == 1 (mod k).

Table of values

List of values

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

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

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