A025323 - OEIS

A025323

Numbers that are the sum of 3 nonzero squares in exactly 3 ways.

54, 66, 81, 86, 89, 99, 101, 110, 114, 126, 131, 149, 150, 162, 166, 173, 174, 179, 182, 185, 186, 216, 219, 221, 222, 225, 227, 233, 237, 241, 242, 245, 258, 264, 274, 275, 286, 291, 302, 305, 309, 315, 318, 323, 324, 334, 338, 344, 347, 349, 356, 361, 366, 377, 396

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

LINKS

David A. Corneth, Table of n, a(n) for n = 1..1069 (first 418 terms from Robert Price, terms < 2*10^6)

David A. Corneth, PARI program

David A. Corneth, Terms below (inclusive) 2*10^6 with the sums of squares

Eric Weisstein's World of Mathematics, Square Number.

Index entries for sequences related to sums of squares

FORMULA

{n: A025427(n) = 3}. - R. J. Mathar, Aug 05 2022

EXAMPLE

182 is a term because 182 = 1^2 + 9^2 + 10^2 = 2^2 + 3^2 + 13^2 = 5^2 + 6^2 + 11^2 and there are no more such sums of three nonzero squares giving 182. - David A. Corneth, Feb 13 2019

MATHEMATICA

Select[Range@ 400, Length@ # == 3 &@ DeleteCases[PowersRepresentations[#, 3, 2], _?(AnyTrue[#, # == 0 &] &)] &] (* Michael De Vlieger, Feb 13 2019 *)

PROG

(PARI) See Corneth link \\ David A. Corneth, Feb 13 2019

CROSSREFS

Cf. A024796, A025427, A025322, A025323, A025324, A025325, A025326, A025327, A025328, A025329, A025330, A025331, A025332, A025333, A025334, A025335, A025336, A025337, A025338.

Sequence in context: A158989 A088489 A025331 * A157934 A335035 A350886

Adjacent sequences: A025320 A025321 A025322 * A025324 A025325 A025326

KEYWORD

nonn

AUTHOR

David W. Wilson

STATUS

approved