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Least integer that can be written as a sum of 3 squares in n nontrivial ways (ignoring order and signs).
2

%I #9 Jun 06 2024 14:58:01

%S 7,0,9,41,81,146,194,306,369,425,594,689,866,1109,1161,1154,1361,1634,

%T 1781,1889,2141,2729,2609,3626,3366,3566,3449,3506,4241,4289,4826,

%U 5066,5381,7034,5561,6254,7229,7829,8186,8069,8126,8609,8921,8774,10386

%N Least integer that can be written as a sum of 3 squares in n nontrivial ways (ignoring order and signs).

%C Essentially the same as A095809. [From _R. J. Mathar_, Aug 02 2008]

%H Wouter Meeussen, <a href="/A122699/b122699.txt">Table of n, a(n) for n = 0..112</a>

%e a(4)=81 since it can be written as 0^2+0^2+9^2, 1^2+4^2+8^2, 3^2+6^2+6^2, 4^2+4^2+7^2.

%t Needs["NumberTheory`NumberTheoryFunctions`"]; Flatten[Position[Table[Length@SumOfSquaresRepresentations[3,n], {n,0,65000}],#,1,1]-1]& /@ Range[0,120]

%Y Cf. A117609.

%K nonn

%O 0,1

%A _Wouter Meeussen_, Oct 21 2006