A080902 - cp's OEIS frontend

A080902 a(1)=1, a(n)=a(n-1)+2 if (n and n+3 are in the sequence), a(n)=a(n-1)+3 otherwise.

n	a(n)
1	1
2	4
3	7
4	9
5	12
6	15
7	18
8	21
9	23
10	26
11	29
12	31
13	34
14	37
15	39
16	42
17	45
18	47
19	50
20	53
21	56
22	59
23	61
24	64
25	67
26	69
27	72
28	75
29	78
30	81
31	83
32	86
33	89
34	91
35	94
36	97
37	100
38	103
39	105
40	108
41	111
42	113
43	116
44	119
45	122
46	125
47	127
48	130
49	133
50	135
51	138
52	141
53	143
54	146
55	149
56	151
57	154
58	157

[1, 4, 7, 9, 12, 15, 18, 21, 23, 26, 29, 31, 34, 37, 39, 42, 45, 47, 50, 53, 56, 59, 61, 64, 67, 69, 72, 75, 78, 81, 83, 86, 89, 91, 94, 97, 100, 103, 105, 108, 111, 113, 116, 119, 122, 125, 127, 130, 133, 135, 138, 141, 143, 146, 149, 151, 154, 157]

cp's OEIS Frontend

A080902 a(1)=1, a(n)=a(n-1)+2 if (n and n+3 are in the sequence), a(n)=a(n-1)+3 otherwise.

Table of values

List of values

n	a(n)
1	1
2	4
3	7
4	9
5	12
6	15
7	18
8	21
9	23
10	26
11	29
12	31
13	34
14	37
15	39
16	42
17	45
18	47
19	50
20	53
21	56
22	59
23	61
24	64
25	67
26	69
27	72
28	75
29	78
30	81
31	83
32	86
33	89
34	91
35	94
36	97
37	100
38	103
39	105
40	108
41	111
42	113
43	116
44	119
45	122
46	125
47	127
48	130
49	133
50	135
51	138
52	141
53	143
54	146
55	149
56	151
57	154
58	157

n	a(n)
1	1
2	4
3	7
4	9
5	12
6	15
7	18
8	21
9	23
10	26
11	29
12	31
13	34
14	37
15	39
16	42
17	45
18	47
19	50
20	53
21	56
22	59
23	61
24	64
25	67
26	69
27	72
28	75
29	78
30	81
31	83
32	86
33	89
34	91
35	94
36	97
37	100
38	103
39	105
40	108
41	111
42	113
43	116
44	119
45	122
46	125
47	127
48	130
49	133
50	135
51	138
52	141
53	143
54	146
55	149
56	151
57	154
58	157

n	a(n)
1	1
2	4
3	7
4	9
5	12
6	15
7	18
8	21
9	23
10	26
11	29
12	31
13	34
14	37
15	39
16	42
17	45
18	47
19	50
20	53
21	56
22	59
23	61
24	64
25	67
26	69
27	72
28	75
29	78
30	81
31	83
32	86
33	89
34	91
35	94
36	97
37	100
38	103
39	105
40	108
41	111
42	113
43	116
44	119
45	122
46	125
47	127
48	130
49	133
50	135
51	138
52	141
53	143
54	146
55	149
56	151
57	154
58	157