A114889 - cp's OEIS frontend

A114889 a(1)=1 and, for n>1, a(n) is the smallest integer greater than a(n-1) such that a(n)+a(i) is not a power of 3, for i=1,..., n-1.

n	a(n)
1	1
2	3
3	4
4	7
5	9
6	10
7	11
8	12
9	13
10	19
11	21
12	22
13	25
14	27
15	28
16	29
17	30
18	31
19	32
20	33
21	34
22	35
23	36
24	37
25	38
26	39
27	40
28	55
29	57
30	58
31	61
32	63
33	64
34	65
35	66
36	67
37	73
38	75
39	76
40	79
41	81
42	82
43	83
44	84
45	85
46	86
47	87
48	88
49	89
50	90
51	91
52	92
53	93
54	94
55	95
56	96
57	97
58	98
59	99
60	100
61	101
62	102
63	103
64	104
65	105
66	106
67	107
68	108

[1, 3, 4, 7, 9, 10, 11, 12, 13, 19, 21, 22, 25, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 55, 57, 58, 61, 63, 64, 65, 66, 67, 73, 75, 76, 79, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108]

cp's OEIS Frontend

A114889 a(1)=1 and, for n>1, a(n) is the smallest integer greater than a(n-1) such that a(n)+a(i) is not a power of 3, for i=1,..., n-1.

Table of values

List of values

n	a(n)
1	1
2	3
3	4
4	7
5	9
6	10
7	11
8	12
9	13
10	19
11	21
12	22
13	25
14	27
15	28
16	29
17	30
18	31
19	32
20	33
21	34
22	35
23	36
24	37
25	38
26	39
27	40
28	55
29	57
30	58
31	61
32	63
33	64
34	65
35	66
36	67
37	73
38	75
39	76
40	79
41	81
42	82
43	83
44	84
45	85
46	86
47	87
48	88
49	89
50	90
51	91
52	92
53	93
54	94
55	95
56	96
57	97
58	98
59	99
60	100
61	101
62	102
63	103
64	104
65	105
66	106
67	107
68	108

n	a(n)
1	1
2	3
3	4
4	7
5	9
6	10
7	11
8	12
9	13
10	19
11	21
12	22
13	25
14	27
15	28
16	29
17	30
18	31
19	32
20	33
21	34
22	35
23	36
24	37
25	38
26	39
27	40
28	55
29	57
30	58
31	61
32	63
33	64
34	65
35	66
36	67
37	73
38	75
39	76
40	79
41	81
42	82
43	83
44	84
45	85
46	86
47	87
48	88
49	89
50	90
51	91
52	92
53	93
54	94
55	95
56	96
57	97
58	98
59	99
60	100
61	101
62	102
63	103
64	104
65	105
66	106
67	107
68	108

n	a(n)
1	1
2	3
3	4
4	7
5	9
6	10
7	11
8	12
9	13
10	19
11	21
12	22
13	25
14	27
15	28
16	29
17	30
18	31
19	32
20	33
21	34
22	35
23	36
24	37
25	38
26	39
27	40
28	55
29	57
30	58
31	61
32	63
33	64
34	65
35	66
36	67
37	73
38	75
39	76
40	79
41	81
42	82
43	83
44	84
45	85
46	86
47	87
48	88
49	89
50	90
51	91
52	92
53	93
54	94
55	95
56	96
57	97
58	98
59	99
60	100
61	101
62	102
63	103
64	104
65	105
66	106
67	107
68	108