A239903 - OEIS

A239903 as a simple table

n	a(n)
0	0
1	1
2	10
3	11
4	12
5	100
6	101
7	110
8	111
9	112
10	120
11	121
12	122
13	123
14	1000
15	1001
16	1010
17	1011
18	1012
19	1100
20	1101
21	1110
22	1111
23	1112
24	1120
25	1121
26	1122
27	1123
28	1200
29	1201
30	1210
31	1211
32	1212
33	1220
34	1221
35	1222
36	1223
37	1230
38	1231
39	1232
40	1233
41	1234
42	10000
43	10001
44	10010
45	10011

[0,1,10,11,12,100,101,110,111,112,120,121,122,123, 1000,1001,1010,1011,1012,1100,1101,1110,1111,1112, 1120,1121,1122,1123,1200,1201,1210,1211,1212,1220, 1221,1222,1223,1230,1231,1232,1233,1234,10000, 10001,10010,10011]