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A024796 Numbers expressible in more than one way as i^2 + j^2 + k^2, where 1 <= i <= j <= k. 24

%I #31 Aug 05 2022 11:08:48

%S 27,33,38,41,51,54,57,59,62,66,69,74,75,77,81,83,86,89,90,94,98,99,

%T 101,102,105,107,108,110,113,114,117,118,121,122,123,125,126,129,131,

%U 132,134,137,138,139,141,146,147,149,150,152,153,154,155,158,161,162,164,165,166,170

%N Numbers expressible in more than one way as i^2 + j^2 + k^2, where 1 <= i <= j <= k.

%C a(n) multiplied by (h^2)/(8*m*a^2) is the n-th energy level exhibiting accidental degeneracy, for a quantum mechanical particle of mass m in a cubic box of side length a (h is Planck's constant). - _A. Timothy Royappa_, Feb 12 2019

%H Robert Price, <a href="/A024796/b024796.txt">Table of n, a(n) for n = 1..8057</a>

%F {n: A025427(n) > 1 }. - _R. J. Mathar_, Aug 05 2022

%t okQ[n_]:= Length[Select[PowersRepresentations[n, 3, 2], !MemberQ[#, 0] &]] > 1; (* _Jinyuan Wang_, Feb 12 2019 *)

%Y Cf. A000408, A007692, A008917, A025322, A025323, A025324, A025325, A025326, A025327, A025328, A025329, A025330, A025331, A025332, A025333, A025334, A025335, A025336, A025337, A025338, A025367, A025427.

%K nonn

%O 1,1

%A _Clark Kimberling_

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Last modified April 24 09:18 EDT 2024. Contains 371935 sequences. (Running on oeis4.)