A025382 Numbers that are the sum of 4 distinct nonzero squares in exactly 7 ways.

190, 198, 231, 255, 290, 303, 326, 335, 358, 369, 381, 385, 418, 425, 439, 475, 481, 491, 497, 499, 529, 553, 557, 563, 569, 587, 593, 612, 613, 619, 644, 661, 676, 733, 760, 792, 1012, 1132, 1160, 1228, 1252, 1304, 1432, 1672, 2448, 2576, 2704, 3040, 3168, 4048

Offset

1,1

Links

Table of n, a(n) for n=1..50.

Index entries for sequences related to sums of squares

Formula

{n: A025443(n) = 7}. - R. J. Mathar, Jun 15 2018

Mathematica

nzsQ[n_]:=Count[IntegerPartitions[n, {4}], _?(FreeQ[#, 0]&&DuplicateFreeQ[#]&&AllTrue[Sqrt[#], IntegerQ]&)]==7; Select[Range[500], nzsQ] (* The program generates the first 20 terms of the sequence. *) (* Harvey P. Dale, Nov 29 2025 *)

Crossrefs

Cf. A025391, A025363.

Sequence in context: A113796 A127994 A025391 * A179518 A186076 A260762

Adjacent sequences: A025379 A025380 A025381 * A025383 A025384 A025385

Keyword

nonn

Author

David W. Wilson

Status

approved