A073653 - cp's OEIS frontend

A073653 a(1)=3, a(2)=5; for n > 2, a(n) = smallest prime not included earlier such that a(n-2) + a(n-1) + a(n) is a prime.

n	a(n)
1	3
2	5
3	11
4	7
5	13
6	17
7	23
8	19
9	29
10	31
11	37
12	41
13	53
14	43
15	61
16	47
17	59
18	67
19	71
20	73
21	79
22	89
23	83
24	97
25	101
26	109
27	103
28	137
29	107
30	139
31	113
32	127
33	149
34	157
35	151
36	131
37	167
38	163
39	173
40	211
41	179
42	181
43	197
44	191
45	199
46	223
47	239
48	229
49	193
50	251
51	233
52	277
53	241
54	269
55	263
56	307
57	227
58	293

[3, 5, 11, 7, 13, 17, 23, 19, 29, 31, 37, 41, 53, 43, 61, 47, 59, 67, 71, 73, 79, 89, 83, 97, 101, 109, 103, 137, 107, 139, 113, 127, 149, 157, 151, 131, 167, 163, 173, 211, 179, 181, 197, 191, 199, 223, 239, 229, 193, 251, 233, 277, 241, 269, 263, 307, 227, 293]

cp's OEIS Frontend

A073653 a(1)=3, a(2)=5; for n > 2, a(n) = smallest prime not included earlier such that a(n-2) + a(n-1) + a(n) is a prime.

Table of values

List of values

n	a(n)
1	3
2	5
3	11
4	7
5	13
6	17
7	23
8	19
9	29
10	31
11	37
12	41
13	53
14	43
15	61
16	47
17	59
18	67
19	71
20	73
21	79
22	89
23	83
24	97
25	101
26	109
27	103
28	137
29	107
30	139
31	113
32	127
33	149
34	157
35	151
36	131
37	167
38	163
39	173
40	211
41	179
42	181
43	197
44	191
45	199
46	223
47	239
48	229
49	193
50	251
51	233
52	277
53	241
54	269
55	263
56	307
57	227
58	293

n	a(n)
1	3
2	5
3	11
4	7
5	13
6	17
7	23
8	19
9	29
10	31
11	37
12	41
13	53
14	43
15	61
16	47
17	59
18	67
19	71
20	73
21	79
22	89
23	83
24	97
25	101
26	109
27	103
28	137
29	107
30	139
31	113
32	127
33	149
34	157
35	151
36	131
37	167
38	163
39	173
40	211
41	179
42	181
43	197
44	191
45	199
46	223
47	239
48	229
49	193
50	251
51	233
52	277
53	241
54	269
55	263
56	307
57	227
58	293

n	a(n)
1	3
2	5
3	11
4	7
5	13
6	17
7	23
8	19
9	29
10	31
11	37
12	41
13	53
14	43
15	61
16	47
17	59
18	67
19	71
20	73
21	79
22	89
23	83
24	97
25	101
26	109
27	103
28	137
29	107
30	139
31	113
32	127
33	149
34	157
35	151
36	131
37	167
38	163
39	173
40	211
41	179
42	181
43	197
44	191
45	199
46	223
47	239
48	229
49	193
50	251
51	233
52	277
53	241
54	269
55	263
56	307
57	227
58	293