%I #5 Feb 05 2016 20:37:45
%S 1,4,7,15,31,39,63,79,111,127,159,207,231,239,255,319,367,399,447,495,
%T 511,519,591,623,639,751,831,879,927,959,1007,1023,1135,1263,1279,
%U 1359,1391,1471,1519,1599,1647,1775,1791,1903,1983,2031,2047,2079,2159,2287
%N Smaller of two consecutive numbers that are not the sum of 3 nonzero squares.
%C {1,2,4,5,7,8,10,13,15,16,20,23,25,28,31,32,..}->{1,4,7,15,31,..}
%H Chai Wah Wu, <a href="/A178615/b178615.txt">Table of n, a(n) for n = 1..10000</a>
%t q=66;q2=q^2+2;lst={};Do[Do[Do[z=a^2+b^2+c^2;If[z<=q2,AppendTo[lst,z]],{c,b,1,-1}],{b,a,1,-1}],{a,q}];lst; u=Union@lst;a=Complement[Range[q^2],u];lst={};Do[If[a[[n+1]]-a[[n]]==1,AppendTo[lst,a[[n]]]],{n,Length[a]-1}];lst
%Y Cf. A004214
%K nonn
%O 1,2
%A _Vladimir Joseph Stephan Orlovsky_, May 30 2010
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