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%I #6 Jul 30 2012 06:48:48
%S 12,219,363,699,1179,2019,2259,3891,4059,6459,5379,10899,13179,10659,
%T 12579,21819,20979,26859,34419,38379,41019,61299,39459,41811,82131,
%U 50379,77451,71379,141099,85491,103971,74571,180411,108339,179739,161139,126819,225099
%N Least number having n orderless representations as p^2 + q^2 + r^2, where p, q, and r are primes.
%H Donovan Johnson, <a href="/A214512/b214512.txt">Table of n, a(n) for n = 1..1000</a>
%t nn = 10^6; ps = Prime[Range[PrimePi[Sqrt[nn]]]]; t = Flatten[Table[ps[[i]]^2 + ps[[j]]^2 + ps[[k]]^2, {i, Length[ps]}, {j, i, Length[ps]}, {k, j, Length[ps]}]]; t = Select[t, # <= nn &]; t2 = Sort[Tally[t]]; u = Union[Transpose[t2][[2]]]; d = Complement[Range[u[[-1]]], u]; If[d == {}, nLim = u[[-1]], nLim = d[[1]]-1]; t3 = Table[Select[t2, #[[2]] == n &, 1][[1]], {n, nLim}]; Transpose[t3][[1]]
%Y Cf. A025414, A025415, A214511, A214513.
%K nonn
%O 1,1
%A _T. D. Noe_, Jul 29 2012
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