A284048 - cp's OEIS frontend

A284048 a(n) is the smallest positive integer not already in the sequence such that a(n) + a(n-1) is a proper prime power (A246547), with a(1) = 1.

n	a(n)
1	1
2	3
3	5
4	4
5	12
6	13
7	14
8	2
9	6
10	10
11	15
12	17
13	8
14	19
15	30
16	34
17	47
18	74
19	7
20	9
21	16
22	11
23	21
24	28
25	36
26	45
27	76
28	49
29	32
30	89
31	39
32	25
33	24
34	40
35	41
36	23
37	26
38	38
39	43
40	78
41	50
42	31
43	18
44	46
45	35
46	29
47	20
48	44
49	37
50	27
51	22
52	42
53	79
54	90
55	153
56	103
57	66
58	55
59	70
60	51
61	77
62	48
63	33
64	88
65	81
66	162
67	94
68	75
69	53
70	68
71	57
72	64
73	61
74	60
75	65
76	56
77	69
78	52
79	73
80	96
81	147

[1, 3, 5, 4, 12, 13, 14, 2, 6, 10, 15, 17, 8, 19, 30, 34, 47, 74, 7, 9, 16, 11, 21, 28, 36, 45, 76, 49, 32, 89, 39, 25, 24, 40, 41, 23, 26, 38, 43, 78, 50, 31, 18, 46, 35, 29, 20, 44, 37, 27, 22, 42, 79, 90, 153, 103, 66, 55, 70, 51, 77, 48, 33, 88, 81, 162, 94, 75, 53, 68, 57, 64, 61, 60, 65, 56, 69, 52, 73, 96, 147]

cp's OEIS Frontend

A284048 a(n) is the smallest positive integer not already in the sequence such that a(n) + a(n-1) is a proper prime power (A246547), with a(1) = 1.

Table of values

List of values

n	a(n)
1	1
2	3
3	5
4	4
5	12
6	13
7	14
8	2
9	6
10	10
11	15
12	17
13	8
14	19
15	30
16	34
17	47
18	74
19	7
20	9
21	16
22	11
23	21
24	28
25	36
26	45
27	76
28	49
29	32
30	89
31	39
32	25
33	24
34	40
35	41
36	23
37	26
38	38
39	43
40	78
41	50
42	31
43	18
44	46
45	35
46	29
47	20
48	44
49	37
50	27
51	22
52	42
53	79
54	90
55	153
56	103
57	66
58	55
59	70
60	51
61	77
62	48
63	33
64	88
65	81
66	162
67	94
68	75
69	53
70	68
71	57
72	64
73	61
74	60
75	65
76	56
77	69
78	52
79	73
80	96
81	147

n	a(n)
1	1
2	3
3	5
4	4
5	12
6	13
7	14
8	2
9	6
10	10
11	15
12	17
13	8
14	19
15	30
16	34
17	47
18	74
19	7
20	9
21	16
22	11
23	21
24	28
25	36
26	45
27	76
28	49
29	32
30	89
31	39
32	25
33	24
34	40
35	41
36	23
37	26
38	38
39	43
40	78
41	50
42	31
43	18
44	46
45	35
46	29
47	20
48	44
49	37
50	27
51	22
52	42
53	79
54	90
55	153
56	103
57	66
58	55
59	70
60	51
61	77
62	48
63	33
64	88
65	81
66	162
67	94
68	75
69	53
70	68
71	57
72	64
73	61
74	60
75	65
76	56
77	69
78	52
79	73
80	96
81	147

n	a(n)
1	1
2	3
3	5
4	4
5	12
6	13
7	14
8	2
9	6
10	10
11	15
12	17
13	8
14	19
15	30
16	34
17	47
18	74
19	7
20	9
21	16
22	11
23	21
24	28
25	36
26	45
27	76
28	49
29	32
30	89
31	39
32	25
33	24
34	40
35	41
36	23
37	26
38	38
39	43
40	78
41	50
42	31
43	18
44	46
45	35
46	29
47	20
48	44
49	37
50	27
51	22
52	42
53	79
54	90
55	153
56	103
57	66
58	55
59	70
60	51
61	77
62	48
63	33
64	88
65	81
66	162
67	94
68	75
69	53
70	68
71	57
72	64
73	61
74	60
75	65
76	56
77	69
78	52
79	73
80	96
81	147