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.

A077189 Smallest concatenation 123...(k-1) k (k-1)...321 (a concatenation of natural numbers from 1 to k and back to 1) that is a multiple of 2n-1, or 0 if no such number exists.

Table of values

n a(n)
1 1
2 12321
3 0
4 12345654321
5 12321
6 121
7 12345654321
8 0

List of values

[1, 12321, 0, 12345654321, 12321, 121, 12345654321, 0]

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

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