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.

A380428 Numbers k for which nonnegative integers x and y exist such that k is the concatenation of x and y as well as k = (x + y)^2.

Table of values

n a(n)
1 81
2 100
3 2025
4 3025
5 88209
6 494209
7 4941729
8 7441984
9 24502500
10 25502500
11 52881984
12 60481729
13 300814336
14 493817284
15 6049417284
16 6832014336
17 20408122449
18 21948126201
19 33058148761
20 35010152100
21 43470165025
22 101558217124
23 108878221089
24 123448227904
25 127194229449
26 152344237969

List of values

[81, 100, 2025, 3025, 88209, 494209, 4941729, 7441984, 24502500, 25502500, 52881984, 60481729, 300814336, 493817284, 6049417284, 6832014336, 20408122449, 21948126201, 33058148761, 35010152100, 43470165025, 101558217124, 108878221089, 123448227904, 127194229449, 152344237969]

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

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