A047420 - OEIS

A047420 as a simple table

n	a(n)
1	0
2	1
3	2
4	3
5	4
6	6
7	8
8	9
9	10
10	11
11	12
12	14
13	16
14	17
15	18
16	19
17	20
18	22
19	24
20	25
21	26
22	27
23	28
24	30
25	32
26	33
27	34
28	35
29	36
30	38
31	40
32	41
33	42
34	43
35	44
36	46
37	48
38	49
39	50
40	51
41	52
42	54
43	56
44	57
45	58
46	59
47	60
48	62
49	64
50	65
51	66
52	67
53	68
54	70
55	72
56	73
57	74
58	75
59	76
60	78
61	80
62	81
63	82
64	83
65	84
66	86
67	88

[0,1,2,3,4,6,8,9,10,11,12,14,16,17,18,19,20,22,24, 25,26,27,28,30,32,33,34,35,36,38,40,41,42,43,44, 46,48,49,50,51,52,54,56,57,58,59,60,62,64,65,66, 67,68,70,72,73,74,75,76,78,80,81,82,83,84,86,88]

n	a(n)
1	0
2	1
3	2
4	3
5	4
6	6
7	8
8	9
9	10
10	11
11	12
12	14
13	16
14	17
15	18
16	19
17	20
18	22
19	24
20	25
21	26
22	27
23	28
24	30
25	32
26	33
27	34
28	35
29	36
30	38
31	40
32	41
33	42
34	43
35	44
36	46
37	48
38	49
39	50
40	51
41	52
42	54
43	56
44	57
45	58
46	59
47	60
48	62
49	64
50	65
51	66
52	67
53	68
54	70
55	72
56	73
57	74
58	75
59	76
60	78
61	80
62	81
63	82
64	83
65	84
66	86
67	88

n	a(n)
1	0
2	1
3	2
4	3
5	4
6	6
7	8
8	9
9	10
10	11
11	12
12	14
13	16
14	17
15	18
16	19
17	20
18	22
19	24
20	25
21	26
22	27
23	28
24	30
25	32
26	33
27	34
28	35
29	36
30	38
31	40
32	41
33	42
34	43
35	44
36	46
37	48
38	49
39	50
40	51
41	52
42	54
43	56
44	57
45	58
46	59
47	60
48	62
49	64
50	65
51	66
52	67
53	68
54	70
55	72
56	73
57	74
58	75
59	76
60	78
61	80
62	81
63	82
64	83
65	84
66	86
67	88

n	a(n)
1	0
2	1
3	2
4	3
5	4
6	6
7	8
8	9
9	10
10	11
11	12
12	14
13	16
14	17
15	18
16	19
17	20
18	22
19	24
20	25
21	26
22	27
23	28
24	30
25	32
26	33
27	34
28	35
29	36
30	38
31	40
32	41
33	42
34	43
35	44
36	46
37	48
38	49
39	50
40	51
41	52
42	54
43	56
44	57
45	58
46	59
47	60
48	62
49	64
50	65
51	66
52	67
53	68
54	70
55	72
56	73
57	74
58	75
59	76
60	78
61	80
62	81
63	82
64	83
65	84
66	86
67	88