A076561 - cp's OEIS frontend

A076561 a(1)=2; a(n>1)= greatest prime divisor of {a(n-1) + n}.

n	a(n)
1	2
2	2
3	5
4	3
5	2
6	2
7	3
8	11
9	5
10	5
11	2
12	7
13	5
14	19
15	17
16	11
17	7
18	5
19	3
20	23
21	11
22	11
23	17
24	41
25	11
26	37
27	2
28	5
29	17
30	47
31	13
32	5
33	19
34	53
35	11
36	47
37	7
38	5
39	11
40	17
41	29
42	71
43	19
44	7
45	13
46	59
47	53
48	101
49	5
50	11
51	31
52	83
53	17
54	71
55	7
56	7
57	2
58	5
59	2
60	31
61	23
62	17
63	5
64	23
65	11
66	11
67	13
68	3
69	3
70	73
71	3
72	5
73	13
74	29
75	13
76	89
77	83
78	23
79	17

[2, 2, 5, 3, 2, 2, 3, 11, 5, 5, 2, 7, 5, 19, 17, 11, 7, 5, 3, 23, 11, 11, 17, 41, 11, 37, 2, 5, 17, 47, 13, 5, 19, 53, 11, 47, 7, 5, 11, 17, 29, 71, 19, 7, 13, 59, 53, 101, 5, 11, 31, 83, 17, 71, 7, 7, 2, 5, 2, 31, 23, 17, 5, 23, 11, 11, 13, 3, 3, 73, 3, 5, 13, 29, 13, 89, 83, 23, 17]

cp's OEIS Frontend

A076561 a(1)=2; a(n>1)= greatest prime divisor of {a(n-1) + n}.

Table of values

List of values

n	a(n)
1	2
2	2
3	5
4	3
5	2
6	2
7	3
8	11
9	5
10	5
11	2
12	7
13	5
14	19
15	17
16	11
17	7
18	5
19	3
20	23
21	11
22	11
23	17
24	41
25	11
26	37
27	2
28	5
29	17
30	47
31	13
32	5
33	19
34	53
35	11
36	47
37	7
38	5
39	11
40	17
41	29
42	71
43	19
44	7
45	13
46	59
47	53
48	101
49	5
50	11
51	31
52	83
53	17
54	71
55	7
56	7
57	2
58	5
59	2
60	31
61	23
62	17
63	5
64	23
65	11
66	11
67	13
68	3
69	3
70	73
71	3
72	5
73	13
74	29
75	13
76	89
77	83
78	23
79	17

n	a(n)
1	2
2	2
3	5
4	3
5	2
6	2
7	3
8	11
9	5
10	5
11	2
12	7
13	5
14	19
15	17
16	11
17	7
18	5
19	3
20	23
21	11
22	11
23	17
24	41
25	11
26	37
27	2
28	5
29	17
30	47
31	13
32	5
33	19
34	53
35	11
36	47
37	7
38	5
39	11
40	17
41	29
42	71
43	19
44	7
45	13
46	59
47	53
48	101
49	5
50	11
51	31
52	83
53	17
54	71
55	7
56	7
57	2
58	5
59	2
60	31
61	23
62	17
63	5
64	23
65	11
66	11
67	13
68	3
69	3
70	73
71	3
72	5
73	13
74	29
75	13
76	89
77	83
78	23
79	17

n	a(n)
1	2
2	2
3	5
4	3
5	2
6	2
7	3
8	11
9	5
10	5
11	2
12	7
13	5
14	19
15	17
16	11
17	7
18	5
19	3
20	23
21	11
22	11
23	17
24	41
25	11
26	37
27	2
28	5
29	17
30	47
31	13
32	5
33	19
34	53
35	11
36	47
37	7
38	5
39	11
40	17
41	29
42	71
43	19
44	7
45	13
46	59
47	53
48	101
49	5
50	11
51	31
52	83
53	17
54	71
55	7
56	7
57	2
58	5
59	2
60	31
61	23
62	17
63	5
64	23
65	11
66	11
67	13
68	3
69	3
70	73
71	3
72	5
73	13
74	29
75	13
76	89
77	83
78	23
79	17