cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A352057 Triangular numbers whose nonzero digits are all the same.

Table of values

n a(n)
1 0
2 1
3 3
4 6
5 10
6 55
7 66
8 300
9 666
10 990
11 3003
12 5050
13 10011
14 66066
15 500500
16 600060
17 50005000
18 5000050000
19 500000500000
20 50000005000000
21 5000000050000000
22 500000000500000000
23 50000000005000000000
24 5000000000050000000000
25 500000000000500000000000
26 50000000000005000000000000

List of values

[0, 1, 3, 6, 10, 55, 66, 300, 666, 990, 3003, 5050, 10011, 66066, 500500, 600060, 50005000, 5000050000, 500000500000, 50000005000000, 5000000050000000, 500000000500000000, 50000000005000000000, 5000000000050000000000, 500000000000500000000000, 50000000000005000000000000]

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement.