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.

A057442 For the numbers k that can be expressed as k = w+x = y*z with w*x = (y+z)^2 where w, x, y, and z are all positive integers, this sequence gives the corresponding values of w*x.

Original entry on oeis.org

64, 81, 100, 324, 225, 576, 2025, 1225, 8100, 8100, 44100, 69696, 13689, 8100, 342225, 18496, 189225, 272484, 1703025, 3744225, 93636, 55225, 15824484, 13017664, 21996100, 5832225, 2005056, 641601, 378225, 627264, 741690756, 2592100, 37088100, 2518433856, 1961604100
Offset: 1

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Author

Naohiro Nomoto, Sep 24 2000

Keywords

Comments

Numbers k are listed (in ascending order) in A057369.

Examples

			From _Jon E. Schoenfield_, May 10 2021: (Start)
The first 10 values of k listed in A057369 and their corresponding values of w, x, y, z, and w*x are as follows:
.
   n    k   w    x  y   z  w*x = a(n)
  --  ---  --  --- --  --  ----------
   1   16   8    8  4   4       64
   2   18   9    9  3   6       81
   3   25   5   20  5   5      100
   4   45   9   36  3  15      324
   5   50   5   45  5  10      225
   6   80   8   72  4  20      576
   7  234   9  225  6  39     2025
   8  250   5  245 10  25     1225
   9  261  36  225  3  87     8100
  10  425  20  405  5  85     8100
(End)
		

Crossrefs

Cf. A057369.

Extensions

More terms from Jinyuan Wang, May 02 2021