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A025414
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a(n) is the smallest number that is the sum of 3 nonzero squares in exactly n ways.
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7
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3, 27, 54, 129, 194, 209, 341, 374, 614, 594, 854, 1106, 1314, 1154, 1286, 1746, 1634, 1881, 2141, 2246, 2609, 2889, 3461, 3366, 3449, 3506, 4241, 4289, 5066, 4826, 5381, 5606, 6569, 5561, 6254, 7601, 8186, 8069, 8714, 8126, 9434, 8921, 8774, 11066, 11574
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OFFSET
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1,1
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COMMENTS
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LINKS
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EXAMPLE
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54 is the smallest number having three partitions into nonzero squares: 54 = 1+4+49 = 4+25+25 = 9+9+36.
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MATHEMATICA
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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)
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PROG
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(Haskell)
import Data.List (elemIndex); import Data.Maybe (fromJust)
a025414 = fromJust . (`elemIndex` a025427_list)
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CROSSREFS
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Cf. A094740 (n having a unique partition into three positive squares), A095812 (greatest number having exactly n partitions into three positive squares).
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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