A381217 - cp's OEIS frontend

A381217 a(n) is the least positive k such that the sum of the reverses of the first k primes is divisible by n.

n	a(n)
1	1
2	1
3	10
4	5
5	2
6	16
7	5
8	20
9	20
10	3
11	9
12	16
13	7
14	5
15	10
16	30
17	4
18	20
19	68
20	44
21	16
22	20
23	9
24	20
25	19
26	7
27	26
28	5
29	47
30	34
31	19
32	30
33	20
34	28
35	99
36	20
37	29
38	68
39	54
40	44
41	86
42	16
43	41
44	20
45	74
46	26
47	40
48	30
49	16
50	50
51	28
52	82
53	97
54	26
55	101
56	51
57	68
58	47
59	6
60	44
61	38
62	53
63	42
64	30
65	7
66	20
67	38
68	28
69	10
70	99
71	110
72	20
73	72
74	121
75	103
76	137
77	189

[1, 1, 10, 5, 2, 16, 5, 20, 20, 3, 9, 16, 7, 5, 10, 30, 4, 20, 68, 44, 16, 20, 9, 20, 19, 7, 26, 5, 47, 34, 19, 30, 20, 28, 99, 20, 29, 68, 54, 44, 86, 16, 41, 20, 74, 26, 40, 30, 16, 50, 28, 82, 97, 26, 101, 51, 68, 47, 6, 44, 38, 53, 42, 30, 7, 20, 38, 28, 10, 99, 110, 20, 72, 121, 103, 137, 189]

cp's OEIS Frontend

A381217 a(n) is the least positive k such that the sum of the reverses of the first k primes is divisible by n.

Table of values

List of values

n	a(n)
1	1
2	1
3	10
4	5
5	2
6	16
7	5
8	20
9	20
10	3
11	9
12	16
13	7
14	5
15	10
16	30
17	4
18	20
19	68
20	44
21	16
22	20
23	9
24	20
25	19
26	7
27	26
28	5
29	47
30	34
31	19
32	30
33	20
34	28
35	99
36	20
37	29
38	68
39	54
40	44
41	86
42	16
43	41
44	20
45	74
46	26
47	40
48	30
49	16
50	50
51	28
52	82
53	97
54	26
55	101
56	51
57	68
58	47
59	6
60	44
61	38
62	53
63	42
64	30
65	7
66	20
67	38
68	28
69	10
70	99
71	110
72	20
73	72
74	121
75	103
76	137
77	189

n	a(n)
1	1
2	1
3	10
4	5
5	2
6	16
7	5
8	20
9	20
10	3
11	9
12	16
13	7
14	5
15	10
16	30
17	4
18	20
19	68
20	44
21	16
22	20
23	9
24	20
25	19
26	7
27	26
28	5
29	47
30	34
31	19
32	30
33	20
34	28
35	99
36	20
37	29
38	68
39	54
40	44
41	86
42	16
43	41
44	20
45	74
46	26
47	40
48	30
49	16
50	50
51	28
52	82
53	97
54	26
55	101
56	51
57	68
58	47
59	6
60	44
61	38
62	53
63	42
64	30
65	7
66	20
67	38
68	28
69	10
70	99
71	110
72	20
73	72
74	121
75	103
76	137
77	189

n	a(n)
1	1
2	1
3	10
4	5
5	2
6	16
7	5
8	20
9	20
10	3
11	9
12	16
13	7
14	5
15	10
16	30
17	4
18	20
19	68
20	44
21	16
22	20
23	9
24	20
25	19
26	7
27	26
28	5
29	47
30	34
31	19
32	30
33	20
34	28
35	99
36	20
37	29
38	68
39	54
40	44
41	86
42	16
43	41
44	20
45	74
46	26
47	40
48	30
49	16
50	50
51	28
52	82
53	97
54	26
55	101
56	51
57	68
58	47
59	6
60	44
61	38
62	53
63	42
64	30
65	7
66	20
67	38
68	28
69	10
70	99
71	110
72	20
73	72
74	121
75	103
76	137
77	189