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.

A077379 Smallest n-digit squarefree number whose internal as well as external digits form a squarefree number greater than 1; or 0 if no such number exists.

Table of values

n a(n)
1 0
2 0
3 123
4 1021
5 10021
6 100021
7 1000021
8 10000021
9 100000021
10 1000000021
11 10000000021
12 100000000021
13 1000000000021
14 10000000000021
15 100000000000021
16 1000000000000021
17 10000000000000021
18 100000000000000021
19 1000000000000000021
20 10000000000000000021
21 100000000000000000021
22 1000000000000000000021

List of values

[0, 0, 123, 1021, 10021, 100021, 1000021, 10000021, 100000021, 1000000021, 10000000021, 100000000021, 1000000000021, 10000000000021, 100000000000021, 1000000000000021, 10000000000000021, 100000000000000021, 1000000000000000021, 10000000000000000021, 100000000000000000021, 1000000000000000000021]

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

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