A078834 - cp's OEIS frontend

A078834 Greatest prime factor of n also contained as binary substring in binary representation of n; a(n)=1, if no such factor exists.

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

[1, 2, 3, 2, 5, 3, 7, 2, 1, 5, 11, 3, 13, 7, 3, 2, 17, 2, 19, 5, 1, 11, 23, 3, 1, 13, 3, 7, 29, 3, 31, 2, 1, 17, 1, 2, 37, 19, 3, 5, 41, 2, 43, 11, 5, 23, 47, 3, 1, 2, 3, 13, 53, 3, 11, 7, 3, 29, 59, 3, 61, 31, 7, 2, 1, 2, 67, 17, 1, 2, 71, 2, 73, 37, 5, 19, 1, 3, 79, 5, 1, 41, 83, 2, 5, 43]

cp's OEIS Frontend

A078834 Greatest prime factor of n also contained as binary substring in binary representation of n; a(n)=1, if no such factor exists.

Table of values

List of values

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

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

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