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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.
2
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
1,1
COMMENTS
Numbers k are listed (in ascending order) in A057369.
EXAMPLE
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.
Sequence in context: A334825 A057372 A374938 * A141817 A008435 A223083
KEYWORD
nonn
AUTHOR
Naohiro Nomoto, Sep 24 2000
EXTENSIONS
More terms from Jinyuan Wang, May 02 2021
STATUS
approved