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.

A138720 Concatenation of k digits 1, k digits 0 and k digits 1, where k is the n-th positive triangular number.

Table of values

n a(n)
1 101
2 111000111
3 111111000000111111
4 111111111100000000001111111111
5 111111111111111000000000000000111111111111111
6 111111111111111111111000000000000000000000111111111111111111111

List of values

[101, 111000111, 111111000000111111, 111111111100000000001111111111, 111111111111111000000000000000111111111111111, 111111111111111111111000000000000000000000111111111111111111111]

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

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