A080903 - cp's OEIS frontend

A080903 a(1)=1; for n>1, a(n)=a(n-1)+4 if n is already in the sequence, a(n)=a(n-1)+2 otherwise.

n	a(n)
1	1
2	3
3	7
4	9
5	11
6	13
7	17
8	19
9	23
10	25
11	29
12	31
13	35
14	37
15	39
16	41
17	45
18	47
19	51
20	53
21	55
22	57
23	61
24	63
25	67
26	69
27	71
28	73
29	77
30	79
31	83
32	85
33	87
34	89
35	93
36	95
37	99
38	101
39	105
40	107
41	111
42	113
43	115
44	117
45	121
46	123
47	127
48	129
49	131
50	133
51	137
52	139
53	143
54	145
55	149
56	151
57	155
58	157
59	159

[1, 3, 7, 9, 11, 13, 17, 19, 23, 25, 29, 31, 35, 37, 39, 41, 45, 47, 51, 53, 55, 57, 61, 63, 67, 69, 71, 73, 77, 79, 83, 85, 87, 89, 93, 95, 99, 101, 105, 107, 111, 113, 115, 117, 121, 123, 127, 129, 131, 133, 137, 139, 143, 145, 149, 151, 155, 157, 159]

cp's OEIS Frontend

A080903 a(1)=1; for n>1, a(n)=a(n-1)+4 if n is already in the sequence, a(n)=a(n-1)+2 otherwise.

Table of values

List of values

n	a(n)
1	1
2	3
3	7
4	9
5	11
6	13
7	17
8	19
9	23
10	25
11	29
12	31
13	35
14	37
15	39
16	41
17	45
18	47
19	51
20	53
21	55
22	57
23	61
24	63
25	67
26	69
27	71
28	73
29	77
30	79
31	83
32	85
33	87
34	89
35	93
36	95
37	99
38	101
39	105
40	107
41	111
42	113
43	115
44	117
45	121
46	123
47	127
48	129
49	131
50	133
51	137
52	139
53	143
54	145
55	149
56	151
57	155
58	157
59	159

n	a(n)
1	1
2	3
3	7
4	9
5	11
6	13
7	17
8	19
9	23
10	25
11	29
12	31
13	35
14	37
15	39
16	41
17	45
18	47
19	51
20	53
21	55
22	57
23	61
24	63
25	67
26	69
27	71
28	73
29	77
30	79
31	83
32	85
33	87
34	89
35	93
36	95
37	99
38	101
39	105
40	107
41	111
42	113
43	115
44	117
45	121
46	123
47	127
48	129
49	131
50	133
51	137
52	139
53	143
54	145
55	149
56	151
57	155
58	157
59	159

n	a(n)
1	1
2	3
3	7
4	9
5	11
6	13
7	17
8	19
9	23
10	25
11	29
12	31
13	35
14	37
15	39
16	41
17	45
18	47
19	51
20	53
21	55
22	57
23	61
24	63
25	67
26	69
27	71
28	73
29	77
30	79
31	83
32	85
33	87
34	89
35	93
36	95
37	99
38	101
39	105
40	107
41	111
42	113
43	115
44	117
45	121
46	123
47	127
48	129
49	131
50	133
51	137
52	139
53	143
54	145
55	149
56	151
57	155
58	157
59	159