A390761 - OEIS

A390761 as a simple table

n	a(n)
1	1
2	2
3	3
4	4
5	5
6	6
7	7
8	8
9	9
10	10
11	1
12	12
13	1113
14	144
15	15
16	1116
17	1771
18	1888
19	1111111119
20	20
21	12
22	2
23	2232
24	24
25	-1
26	2226
27	2772
28	288
29	2222222292
30	30
31	1113
32	2232
33	3
34	3444
35	3555
36	36
37	37737
38	3888
39	3339
40	40
41	144
42	24
43	3444
44	4
45	-1
46	4464
47	44744
48	48
49	4444444944
50	50
51	15
52	-1
53	3555

[1,2,3,4,5,6,7,8,9,10,1,12,1113,144,15,1116,1771, 1888,1111111119,20,12,2,2232,24,-1,2226,2772,288, 2222222292,30,1113,2232,3,3444,3555,36,37737,3888, 3339,40,144,24,3444,4,-1,4464,44744,48,4444444944, 50,15,-1,3555]