A247021 - cp's OEIS frontend

A247021 Triangular numbers composed of only digits with line segments or both line segments and curves {1, 2, 4, 5, 7}.

n	a(n)
1	1
2	15
3	21
4	45
5	55
6	171
7	741
8	1225
9	1275
10	1711
11	2145
12	2211
13	2415
14	2775
15	5151
16	11175
17	15225
18	21115
19	22155
20	25425
21	44551
22	45451
23	72771
24	77421
25	112575
26	121771
27	124251
28	125751
29	151525
30	211575
31	221445
32	222111
33	224115
34	227475
35	254541
36	255255
37	417241
38	451725
39	551775
40	577275

[1, 15, 21, 45, 55, 171, 741, 1225, 1275, 1711, 2145, 2211, 2415, 2775, 5151, 11175, 15225, 21115, 22155, 25425, 44551, 45451, 72771, 77421, 112575, 121771, 124251, 125751, 151525, 211575, 221445, 222111, 224115, 227475, 254541, 255255, 417241, 451725, 551775, 577275]

cp's OEIS Frontend

A247021 Triangular numbers composed of only digits with line segments or both line segments and curves {1, 2, 4, 5, 7}.

Table of values

List of values