A033557 - cp's OEIS frontend

A033557 2n - {largest prime < n}.

n	a(n)
3	4
4	5
5	7
6	7
7	9
8	9
9	11
10	13
11	15
12	13
13	15
14	15
15	17
16	19
17	21
18	19
19	21
20	21
21	23
22	25
23	27
24	25
25	27
26	29
27	31
28	33
29	35
30	31
31	33
32	33
33	35
34	37
35	39
36	41
37	43
38	39
39	41
40	43
41	45
42	43
43	45
44	45
45	47
46	49
47	51
48	49
49	51
50	53
51	55
52	57
53	59
54	55
55	57
56	59
57	61
58	63

[4, 5, 7, 7, 9, 9, 11, 13, 15, 13, 15, 15, 17, 19, 21, 19, 21, 21, 23, 25, 27, 25, 27, 29, 31, 33, 35, 31, 33, 33, 35, 37, 39, 41, 43, 39, 41, 43, 45, 43, 45, 45, 47, 49, 51, 49, 51, 53, 55, 57, 59, 55, 57, 59, 61, 63]

cp's OEIS Frontend

A033557 2n - {largest prime < n}.

Table of values

List of values

n	a(n)
3	4
4	5
5	7
6	7
7	9
8	9
9	11
10	13
11	15
12	13
13	15
14	15
15	17
16	19
17	21
18	19
19	21
20	21
21	23
22	25
23	27
24	25
25	27
26	29
27	31
28	33
29	35
30	31
31	33
32	33
33	35
34	37
35	39
36	41
37	43
38	39
39	41
40	43
41	45
42	43
43	45
44	45
45	47
46	49
47	51
48	49
49	51
50	53
51	55
52	57
53	59
54	55
55	57
56	59
57	61
58	63

n	a(n)
3	4
4	5
5	7
6	7
7	9
8	9
9	11
10	13
11	15
12	13
13	15
14	15
15	17
16	19
17	21
18	19
19	21
20	21
21	23
22	25
23	27
24	25
25	27
26	29
27	31
28	33
29	35
30	31
31	33
32	33
33	35
34	37
35	39
36	41
37	43
38	39
39	41
40	43
41	45
42	43
43	45
44	45
45	47
46	49
47	51
48	49
49	51
50	53
51	55
52	57
53	59
54	55
55	57
56	59
57	61
58	63

n	a(n)
3	4
4	5
5	7
6	7
7	9
8	9
9	11
10	13
11	15
12	13
13	15
14	15
15	17
16	19
17	21
18	19
19	21
20	21
21	23
22	25
23	27
24	25
25	27
26	29
27	31
28	33
29	35
30	31
31	33
32	33
33	35
34	37
35	39
36	41
37	43
38	39
39	41
40	43
41	45
42	43
43	45
44	45
45	47
46	49
47	51
48	49
49	51
50	53
51	55
52	57
53	59
54	55
55	57
56	59
57	61
58	63