A174977 - cp's OEIS frontend

A174977 Natural numbers n = n(k) with property that string "2" appears k-times in concatenation Conc(1;n) := 1//2// ... //n (k, n = 1, 2, ...) or 0 if n(k) does not exist.

n	a(n)
1	2
2	12
3	20
4	21
5	0
6	22
7	23
8	24
9	25
10	26
11	27
12	28
13	29
14	32
15	42
16	52
17	62
18	72
19	82
20	92
21	102
22	112
23	120
24	121
25	0
26	122
27	123
28	124
29	125
30	126
31	127
32	128
33	129
34	132
35	142
36	152
37	162
38	172
39	182
40	192
41	200
42	201
43	0
44	202
45	203
46	204
47	205
48	206
49	207
50	208
51	209
52	210
53	211
54	0
55	212
56	0
57	220
58	0
59	221
60	0
61	0

[2, 12, 20, 21, 0, 22, 23, 24, 25, 26, 27, 28, 29, 32, 42, 52, 62, 72, 82, 92, 102, 112, 120, 121, 0, 122, 123, 124, 125, 126, 127, 128, 129, 132, 142, 152, 162, 172, 182, 192, 200, 201, 0, 202, 203, 204, 205, 206, 207, 208, 209, 210, 211, 0, 212, 0, 220, 0, 221, 0, 0]

cp's OEIS Frontend

A174977 Natural numbers n = n(k) with property that string "2" appears k-times in concatenation Conc(1;n) := 1//2// ... //n (k, n = 1, 2, ...) or 0 if n(k) does not exist.

Table of values

List of values

n	a(n)
1	2
2	12
3	20
4	21
5	0
6	22
7	23
8	24
9	25
10	26
11	27
12	28
13	29
14	32
15	42
16	52
17	62
18	72
19	82
20	92
21	102
22	112
23	120
24	121
25	0
26	122
27	123
28	124
29	125
30	126
31	127
32	128
33	129
34	132
35	142
36	152
37	162
38	172
39	182
40	192
41	200
42	201
43	0
44	202
45	203
46	204
47	205
48	206
49	207
50	208
51	209
52	210
53	211
54	0
55	212
56	0
57	220
58	0
59	221
60	0
61	0

n	a(n)
1	2
2	12
3	20
4	21
5	0
6	22
7	23
8	24
9	25
10	26
11	27
12	28
13	29
14	32
15	42
16	52
17	62
18	72
19	82
20	92
21	102
22	112
23	120
24	121
25	0
26	122
27	123
28	124
29	125
30	126
31	127
32	128
33	129
34	132
35	142
36	152
37	162
38	172
39	182
40	192
41	200
42	201
43	0
44	202
45	203
46	204
47	205
48	206
49	207
50	208
51	209
52	210
53	211
54	0
55	212
56	0
57	220
58	0
59	221
60	0
61	0

n	a(n)
1	2
2	12
3	20
4	21
5	0
6	22
7	23
8	24
9	25
10	26
11	27
12	28
13	29
14	32
15	42
16	52
17	62
18	72
19	82
20	92
21	102
22	112
23	120
24	121
25	0
26	122
27	123
28	124
29	125
30	126
31	127
32	128
33	129
34	132
35	142
36	152
37	162
38	172
39	182
40	192
41	200
42	201
43	0
44	202
45	203
46	204
47	205
48	206
49	207
50	208
51	209
52	210
53	211
54	0
55	212
56	0
57	220
58	0
59	221
60	0
61	0