A025379 Numbers that are the sum of 4 distinct nonzero squares in exactly 4 ways.

142, 158, 162, 165, 182, 183, 195, 206, 207, 214, 215, 218, 226, 239, 243, 245, 259, 260, 262, 263, 289, 298, 299, 300, 301, 317, 324, 329, 331, 337, 355, 364, 372, 373, 389, 409, 428, 436, 452, 461, 484, 532, 548, 556, 568, 580, 632, 648, 728, 824, 856, 872, 904

Offset: 1

Author

David W. Wilson

Keywords

• nonn

Links

• Harvey P. Dale, Table of n, a(n) for n = 1..100
• Index entries for sequences related to sums of squares

Crossrefs

Cf. A025388, A025360.

Programs

Mathematica

With[{nn=40},Select[Union[Select[Tally[Total/@Subsets[Range[nn]^2,{4}]], #[[2]] == 4&][[All,1]]],#<=nn^2-14&]] (* Harvey P. Dale, May 03 2020 *)

Formula

{n: A025443(n) = 4}. - R. J. Mathar, Jun 15 2018