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.

A272672 Numbers n such that the decimal concatenations 1n and 2n are both squares.

Table of values

n a(n)
1 1025
2 102500
3 1390625
4 10250000
5 96700625
6 139062500
7 1025000000
8 9670062500
9 13906250000
10 102500000000
11 967006250000
12 1390625000000
13 10250000000000
14 17654697265625
15 96700625000000
16 139062500000000
17 910400191015625

List of values

[1025, 102500, 1390625, 10250000, 96700625, 139062500, 1025000000, 9670062500, 13906250000, 102500000000, 967006250000, 1390625000000, 10250000000000, 17654697265625, 96700625000000, 139062500000000, 910400191015625]

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

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