A158520 - OEIS

A158520 as a simple table

n	a(n)
1	0
2	1
3	2
4	3
5	4
6	5
7	6
8	10
9	11
10	12
11	13
12	24
13	25
14	26
15	50
16	51
17	52
18	53
19	103
20	104
21	105
22	106
23	210
24	211
25	212
26	422
27	423
28	424
29	425
30	848
31	849
32	850
33	1698
34	1699
35	1700
36	3399
37	3400
38	3401
39	6800
40	6801
41	6802
42	6803
43	13604
44	13605
45	13606
46	27210
47	27211
48	27212
49	27213

[0,1,2,3,4,5,6,10,11,12,13,24,25,26,50,51,52,53, 103,104,105,106,210,211,212,422,423,424,425,848, 849,850,1698,1699,1700,3399,3400,3401,6800,6801, 6802,6803,13604,13605,13606,27210,27211,27212, 27213]