A137281 - cp's OEIS frontend

A137281 Numbers k such that T(k) is not divisible by T(i), 1 < i < k, where T(k) = k-th triangular number A000217(k).

n	a(n)
1	2
2	4
3	7
4	10
5	13
6	16
7	22
8	25
9	28
10	31
11	34
12	37
13	43
14	46
15	49
16	52
17	58
18	61
19	67
20	70
21	73
22	76
23	82
24	85
25	88
26	94
27	97
28	103
29	106
30	118
31	121
32	127
33	130
34	133
35	136
36	142
37	145
38	148
39	151
40	157
41	163
42	166
43	169
44	172
45	178
46	187
47	190
48	193
49	196
50	202
51	205
52	208
53	211
54	214
55	217
56	226
57	229
58	232
59	238
60	241

[2, 4, 7, 10, 13, 16, 22, 25, 28, 31, 34, 37, 43, 46, 49, 52, 58, 61, 67, 70, 73, 76, 82, 85, 88, 94, 97, 103, 106, 118, 121, 127, 130, 133, 136, 142, 145, 148, 151, 157, 163, 166, 169, 172, 178, 187, 190, 193, 196, 202, 205, 208, 211, 214, 217, 226, 229, 232, 238, 241]

cp's OEIS Frontend

A137281 Numbers k such that T(k) is not divisible by T(i), 1 < i < k, where T(k) = k-th triangular number A000217(k).

Table of values

List of values

n	a(n)
1	2
2	4
3	7
4	10
5	13
6	16
7	22
8	25
9	28
10	31
11	34
12	37
13	43
14	46
15	49
16	52
17	58
18	61
19	67
20	70
21	73
22	76
23	82
24	85
25	88
26	94
27	97
28	103
29	106
30	118
31	121
32	127
33	130
34	133
35	136
36	142
37	145
38	148
39	151
40	157
41	163
42	166
43	169
44	172
45	178
46	187
47	190
48	193
49	196
50	202
51	205
52	208
53	211
54	214
55	217
56	226
57	229
58	232
59	238
60	241

n	a(n)
1	2
2	4
3	7
4	10
5	13
6	16
7	22
8	25
9	28
10	31
11	34
12	37
13	43
14	46
15	49
16	52
17	58
18	61
19	67
20	70
21	73
22	76
23	82
24	85
25	88
26	94
27	97
28	103
29	106
30	118
31	121
32	127
33	130
34	133
35	136
36	142
37	145
38	148
39	151
40	157
41	163
42	166
43	169
44	172
45	178
46	187
47	190
48	193
49	196
50	202
51	205
52	208
53	211
54	214
55	217
56	226
57	229
58	232
59	238
60	241

n	a(n)
1	2
2	4
3	7
4	10
5	13
6	16
7	22
8	25
9	28
10	31
11	34
12	37
13	43
14	46
15	49
16	52
17	58
18	61
19	67
20	70
21	73
22	76
23	82
24	85
25	88
26	94
27	97
28	103
29	106
30	118
31	121
32	127
33	130
34	133
35	136
36	142
37	145
38	148
39	151
40	157
41	163
42	166
43	169
44	172
45	178
46	187
47	190
48	193
49	196
50	202
51	205
52	208
53	211
54	214
55	217
56	226
57	229
58	232
59	238
60	241