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.

A321687 a(n) = (2*n+1)-digit palindrome formed by first concatenating A158289(i) for i=1..n+1 and then A158289(n-j) for j=1..n.

Table of values

n a(n)
0 1
1 121
2 12321
3 1234321
4 123454321
5 12345654321
6 1234567654321
7 123456787654321
8 12345678987654321
9 1234567898987654321
10 123456789878987654321
11 12345678987678987654321
12 1234567898765678987654321
13 123456789876545678987654321
14 12345678987654345678987654321

List of values

[1, 121, 12321, 1234321, 123454321, 12345654321, 1234567654321, 123456787654321, 12345678987654321, 1234567898987654321, 123456789878987654321, 12345678987678987654321, 1234567898765678987654321, 123456789876545678987654321, 12345678987654345678987654321]

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

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