A193996 - OEIS

A193996 as a simple table

n	a(n)
1	4
2	16
3	20
4	37
5	42
6	58
7	89
8	145
9	78999
10	79899
11	79989
12	79998
13	87999
14	89799
15	89979
16	89997
17	97899
18	97989
19	97998
20	98799
21	98979
22	98997
23	99789
24	99798
25	99879
26	99897
27	99978
28	99987
29	378999
30	379899
31	379989
32	379998
33	387999
34	389799
35	389979
36	389997
37	389999
38	397899
39	397989

[4,16,20,37,42,58,89,145,78999,79899,79989,79998, 87999,89799,89979,89997,97899,97989,97998,98799, 98979,98997,99789,99798,99879,99897,99978,99987, 378999,379899,379989,379998,387999,389799,389979, 389997,389999,397899,397989]