A338941 - cp's OEIS frontend

A338941 a(1)=1. For n >= 2, let S be the sum of all prime digits in a(1), a(2), ... a(n-1) and let C be the next nonprime number not already in the sequence. If S is a prime less than C and is not already a term of the sequence, a(n) = S. Otherwise, a(n) = C.

n	a(n)
1	1
2	4
3	6
4	8
5	9
6	10
7	12
8	2
9	14
10	15
11	16
12	18
13	20
14	11
15	21
16	13
17	22
18	24
19	25
20	26
21	27
22	28
23	30
24	32
25	33
26	34
27	35
28	36
29	38
30	39
31	40
32	42
33	44
34	45
35	46
36	48
37	49
38	50
39	51
40	52
41	54
42	55
43	56
44	57
45	58
46	60
47	62
48	63
49	64
50	65
51	66
52	68
53	69
54	70
55	72
56	74
57	75
58	76
59	77
60	78
61	80
62	81
63	82
64	84
65	85
66	86
67	87
68	88
69	90

[1, 4, 6, 8, 9, 10, 12, 2, 14, 15, 16, 18, 20, 11, 21, 13, 22, 24, 25, 26, 27, 28, 30, 32, 33, 34, 35, 36, 38, 39, 40, 42, 44, 45, 46, 48, 49, 50, 51, 52, 54, 55, 56, 57, 58, 60, 62, 63, 64, 65, 66, 68, 69, 70, 72, 74, 75, 76, 77, 78, 80, 81, 82, 84, 85, 86, 87, 88, 90]

cp's OEIS Frontend

A338941 a(1)=1. For n >= 2, let S be the sum of all prime digits in a(1), a(2), ... a(n-1) and let C be the next nonprime number not already in the sequence. If S is a prime less than C and is not already a term of the sequence, a(n) = S. Otherwise, a(n) = C.

Table of values

List of values

n	a(n)
1	1
2	4
3	6
4	8
5	9
6	10
7	12
8	2
9	14
10	15
11	16
12	18
13	20
14	11
15	21
16	13
17	22
18	24
19	25
20	26
21	27
22	28
23	30
24	32
25	33
26	34
27	35
28	36
29	38
30	39
31	40
32	42
33	44
34	45
35	46
36	48
37	49
38	50
39	51
40	52
41	54
42	55
43	56
44	57
45	58
46	60
47	62
48	63
49	64
50	65
51	66
52	68
53	69
54	70
55	72
56	74
57	75
58	76
59	77
60	78
61	80
62	81
63	82
64	84
65	85
66	86
67	87
68	88
69	90

n	a(n)
1	1
2	4
3	6
4	8
5	9
6	10
7	12
8	2
9	14
10	15
11	16
12	18
13	20
14	11
15	21
16	13
17	22
18	24
19	25
20	26
21	27
22	28
23	30
24	32
25	33
26	34
27	35
28	36
29	38
30	39
31	40
32	42
33	44
34	45
35	46
36	48
37	49
38	50
39	51
40	52
41	54
42	55
43	56
44	57
45	58
46	60
47	62
48	63
49	64
50	65
51	66
52	68
53	69
54	70
55	72
56	74
57	75
58	76
59	77
60	78
61	80
62	81
63	82
64	84
65	85
66	86
67	87
68	88
69	90

n	a(n)
1	1
2	4
3	6
4	8
5	9
6	10
7	12
8	2
9	14
10	15
11	16
12	18
13	20
14	11
15	21
16	13
17	22
18	24
19	25
20	26
21	27
22	28
23	30
24	32
25	33
26	34
27	35
28	36
29	38
30	39
31	40
32	42
33	44
34	45
35	46
36	48
37	49
38	50
39	51
40	52
41	54
42	55
43	56
44	57
45	58
46	60
47	62
48	63
49	64
50	65
51	66
52	68
53	69
54	70
55	72
56	74
57	75
58	76
59	77
60	78
61	80
62	81
63	82
64	84
65	85
66	86
67	87
68	88
69	90