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.

A355277 Largest n-digit number k with only odd digits such that the k-th triangular number also has only odd digits.

Table of values

n a(n)
1 5
2 17
3 177
4 5573
5 79137
6 791377
7 7913777
8 79971937
9 557335733
10 5995957537
11 59995599137
12 599591791137
13 7991739957973
14 79971739957537
15 799739357539937
16 7991713197753777
17 79991971791119137
18 799999173991317537
19 7997391313911797973

List of values

[5, 17, 177, 5573, 79137, 791377, 7913777, 79971937, 557335733, 5995957537, 59995599137, 599591791137, 7991739957973, 79971739957537, 799739357539937, 7991713197753777, 79991971791119137, 799999173991317537, 7997391313911797973]

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

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