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%I #29 Dec 10 2016 17:00:34
%S 4,5,10,11,13,15,20,21,26,27,29,31,34,38,40,42,43,49,50,54,56,58,59,
%T 64,67,69,71,75,77,78,80,85,86,90,91,95,99,101,102,104,108,111,113,
%U 116,117,120,123,128,129,132,133,136,141,143,144,146,151,152,154,156,160
%N Indices of Greedy Queens (see A065188) below main diagonal.
%C The word "below" in the definition is somewhat ambiguous. More precisely, this is the list of n such that A065188(n) < n. - _N. J. A. Sloane_, Aug 18 2016
%C For Greedy Queens that do not attack along antidiagonals, the analogous sequence of indices is A026352.
%H N. J. A. Sloane, <a href="/A199134/b199134.txt">Table of n, a(n) for n = 1..19098</a>
%e Greedy Queens take positions (1,1) (2,3) (3,5) (4,2) (5,4) (6,9) ... and the 4th and 5th are below the main diagonal, so a(1)=4 and a(2)=5.
%t <<DiscreteMath`Combinatorica`;
%t base2=Table[{i,j},{i,0,256},{j,Floor[i/2],2i}];
%t base3=DeleteCases[base2,{k_,l_}/;Or[l<-2+Floor[k/GoldenRatio],l>2+Floor[k*GoldenRatio],And[l>3+Floor[k/GoldenRatio],l<Floor[k*GoldenRatio]]],2 ];
%t standardQueens=Backtrack[base3,(And[UnsameQ@@ First /@ #,UnsameQ@@ Last/@ #,UnsameQ@@ Subtract@@@ #,UnsameQ@@ Plus@@@ #])&,True&,One];
%t Position[Subtract@@@ standardQueens,_?Positive]//Flatten
%Y Cf. A065188, A026352, A275893 (another version).
%Y A275884 is the complementary sequence.
%Y For runs see A275885, A275886.
%K nonn
%O 1,1
%A _Wouter Meeussen_, Nov 04 2011
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