A321366 - cp's OEIS frontend

A321366 a(n) is the least integer k greater than 1 such that n divides binomial(k, 2) = A000217(k-1).

n	a(n)
1	2
2	4
3	3
4	8
5	5
6	4
7	7
8	16
9	9
10	5
11	11
12	9
13	13
14	8
15	6
16	32
17	17
18	9
19	19
20	16
21	7
22	12
23	23
24	16
25	25
26	13
27	27
28	8
29	29
30	16
31	31
32	64
33	12
34	17
35	15
36	9
37	37
38	20
39	13
40	16
41	41
42	21
43	43
44	33
45	10
46	24
47	47
48	33
49	49
50	25
51	18
52	40
53	53
54	28
55	11
56	49
57	19
58	29
59	59
60	16
61	61
62	32
63	28
64	128
65	26

[2, 4, 3, 8, 5, 4, 7, 16, 9, 5, 11, 9, 13, 8, 6, 32, 17, 9, 19, 16, 7, 12, 23, 16, 25, 13, 27, 8, 29, 16, 31, 64, 12, 17, 15, 9, 37, 20, 13, 16, 41, 21, 43, 33, 10, 24, 47, 33, 49, 25, 18, 40, 53, 28, 11, 49, 19, 29, 59, 16, 61, 32, 28, 128, 26]

cp's OEIS Frontend

A321366 a(n) is the least integer k greater than 1 such that n divides binomial(k, 2) = A000217(k-1).

Table of values

List of values

n	a(n)
1	2
2	4
3	3
4	8
5	5
6	4
7	7
8	16
9	9
10	5
11	11
12	9
13	13
14	8
15	6
16	32
17	17
18	9
19	19
20	16
21	7
22	12
23	23
24	16
25	25
26	13
27	27
28	8
29	29
30	16
31	31
32	64
33	12
34	17
35	15
36	9
37	37
38	20
39	13
40	16
41	41
42	21
43	43
44	33
45	10
46	24
47	47
48	33
49	49
50	25
51	18
52	40
53	53
54	28
55	11
56	49
57	19
58	29
59	59
60	16
61	61
62	32
63	28
64	128
65	26

n	a(n)
1	2
2	4
3	3
4	8
5	5
6	4
7	7
8	16
9	9
10	5
11	11
12	9
13	13
14	8
15	6
16	32
17	17
18	9
19	19
20	16
21	7
22	12
23	23
24	16
25	25
26	13
27	27
28	8
29	29
30	16
31	31
32	64
33	12
34	17
35	15
36	9
37	37
38	20
39	13
40	16
41	41
42	21
43	43
44	33
45	10
46	24
47	47
48	33
49	49
50	25
51	18
52	40
53	53
54	28
55	11
56	49
57	19
58	29
59	59
60	16
61	61
62	32
63	28
64	128
65	26

n	a(n)
1	2
2	4
3	3
4	8
5	5
6	4
7	7
8	16
9	9
10	5
11	11
12	9
13	13
14	8
15	6
16	32
17	17
18	9
19	19
20	16
21	7
22	12
23	23
24	16
25	25
26	13
27	27
28	8
29	29
30	16
31	31
32	64
33	12
34	17
35	15
36	9
37	37
38	20
39	13
40	16
41	41
42	21
43	43
44	33
45	10
46	24
47	47
48	33
49	49
50	25
51	18
52	40
53	53
54	28
55	11
56	49
57	19
58	29
59	59
60	16
61	61
62	32
63	28
64	128
65	26