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%I #16 Feb 26 2015 16:58:48
%S 3,27,54,129,194,209,341,374,614,594,854,1106,1314,1154,1286,1746,
%T 1634,1881,2141,2246,2609,2889,3461,3366,3449,3506,4241,4289,5066,
%U 4826,5381,5606,6569,5561,6254,7601,8186,8069,8714,8126,9434,8921,8774,11066,11574
%N a(n) is the smallest number that is the sum of 3 nonzero squares in exactly n ways.
%C A025427(a(n)) = n and A025427(m) != n for m < a(n). - _Reinhard Zumkeller_, Feb 26 2015
%H Donovan Johnson, <a href="/A025414/b025414.txt">Table of n, a(n) for n = 1..1000</a>
%H <a href="/index/Su#ssq">Index entries for sequences related to sums of squares</a>
%e 54 is the smallest number having three partitions into nonzero squares: 54 = 1+4+49 = 4+25+25 = 9+9+36.
%t lim=200; nLst=Table[0, {lim^2}]; Do[n=a^2+b^2+c^2; If[n>0 && n<lim^2, nLst[[n]]++ ], {a, lim}, {b, a, Sqrt[lim^2-a^2]}, {c, b, Sqrt[lim^2-a^2-b^2]}]; u=Union[nLst]; kMax=First[Complement[1+Range[u[[ -1]]], u]]-1; Table[First[Flatten[Position[nLst, k]]], {k, kMax}] (T. D. Noe)
%o (Haskell)
%o import Data.List (elemIndex); import Data.Maybe (fromJust)
%o a025414 = fromJust . (`elemIndex` a025427_list)
%o -- _Reinhard Zumkeller_, Feb 26 2015
%Y Cf. A094740 (n having a unique partition into three positive squares), A095812 (greatest number having exactly n partitions into three positive squares).
%Y Cf. A025427.
%K nonn
%O 1,1
%A _David W. Wilson_
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