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.

A380792 a(n) is the largest triangular number that is the concatenation of two n-digit numbers 2*x and x.

Table of values

n a(n)
1 21
2 9045
3 890445
4 88904445
5 8889044445
6 888890444445
7 88888904444445
8 8888889044444445
9 888888890444444445
10 88888888904444444445
11 8888888889044444444445
12 973609801090486804900545
13 88888888888904444444444445
14 8888888888889044444444444445
15 931379640537060465689820268530

List of values

[21, 9045, 890445, 88904445, 8889044445, 888890444445, 88888904444445, 8888889044444445, 888888890444444445, 88888888904444444445, 8888888889044444444445, 973609801090486804900545, 88888888888904444444444445, 8888888888889044444444444445, 931379640537060465689820268530]

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

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