A131261 - cp's OEIS frontend

A131261 a(0)=3; for n>0, a(n) = smallest odd prime not occurring earlier in the sequence such that a(n-1)+a(n) is a multiple of n.

n	a(n)
0	3
1	5
2	7
3	11
4	13
5	17
6	19
7	23
8	41
9	31
10	29
11	37
12	47
13	83
14	43
15	107
16	53
17	151
18	101
19	89
20	71
21	97
22	79
23	59
24	61
25	139
26	173
27	313
28	163
29	127
30	113
31	73
32	311
33	283
34	193
35	157
36	131
37	239
38	103
39	443
40	197
41	541
42	257
43	431
44	229
45	401
46	887
47	241
48	191
49	397
50	353
51	463
52	109
53	421
54	227
55	433
56	631
57	167

[3, 5, 7, 11, 13, 17, 19, 23, 41, 31, 29, 37, 47, 83, 43, 107, 53, 151, 101, 89, 71, 97, 79, 59, 61, 139, 173, 313, 163, 127, 113, 73, 311, 283, 193, 157, 131, 239, 103, 443, 197, 541, 257, 431, 229, 401, 887, 241, 191, 397, 353, 463, 109, 421, 227, 433, 631, 167]

cp's OEIS Frontend

A131261 a(0)=3; for n>0, a(n) = smallest odd prime not occurring earlier in the sequence such that a(n-1)+a(n) is a multiple of n.

Table of values

List of values

n	a(n)
0	3
1	5
2	7
3	11
4	13
5	17
6	19
7	23
8	41
9	31
10	29
11	37
12	47
13	83
14	43
15	107
16	53
17	151
18	101
19	89
20	71
21	97
22	79
23	59
24	61
25	139
26	173
27	313
28	163
29	127
30	113
31	73
32	311
33	283
34	193
35	157
36	131
37	239
38	103
39	443
40	197
41	541
42	257
43	431
44	229
45	401
46	887
47	241
48	191
49	397
50	353
51	463
52	109
53	421
54	227
55	433
56	631
57	167

n	a(n)
0	3
1	5
2	7
3	11
4	13
5	17
6	19
7	23
8	41
9	31
10	29
11	37
12	47
13	83
14	43
15	107
16	53
17	151
18	101
19	89
20	71
21	97
22	79
23	59
24	61
25	139
26	173
27	313
28	163
29	127
30	113
31	73
32	311
33	283
34	193
35	157
36	131
37	239
38	103
39	443
40	197
41	541
42	257
43	431
44	229
45	401
46	887
47	241
48	191
49	397
50	353
51	463
52	109
53	421
54	227
55	433
56	631
57	167

n	a(n)
0	3
1	5
2	7
3	11
4	13
5	17
6	19
7	23
8	41
9	31
10	29
11	37
12	47
13	83
14	43
15	107
16	53
17	151
18	101
19	89
20	71
21	97
22	79
23	59
24	61
25	139
26	173
27	313
28	163
29	127
30	113
31	73
32	311
33	283
34	193
35	157
36	131
37	239
38	103
39	443
40	197
41	541
42	257
43	431
44	229
45	401
46	887
47	241
48	191
49	397
50	353
51	463
52	109
53	421
54	227
55	433
56	631
57	167