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a(n) = A275901(n) + A275902(n).
5

%I #5 Oct 03 2016 17:49:37

%S 0,3,4,6,7,13,14,16,17,18,19,22,23,29,30,33,34,39,40,42,43,44,45,48,

%T 49,53,55,58,59,61,62,64,67,68,71,76,77,80,81,84,85,88,89,92,93,94,95,

%U 100,102,105,107,110,112,113,115,118,119,121,122,124,126,127,131,134,135,137,138,142,143,146,147,152,154,157,158,160,161,163,165,166,168,171

%N a(n) = A275901(n) + A275902(n).

%C Specifies which diagonals the queens in A275901 and A275902 lie on.

%p # To get 10000 terms of A275902 (xx), A275901 (yy), A276783 (ss), -A276325 (dd)

%p M1:=100000; M2:=22000; M3:=10000;

%p xx:=Array(0..M1,0); yy:=Array(0..M1,0); ss:=Array(0..M1,0); dd:=Array(0..M1,0);

%p xx[0]:=0; yy[0]:=0; ss[0]:=0; dd[0]:=0;

%p for n from 1 to M2 do

%p sw:=-1;

%p for s from ss[n-1]+1 to M2 do

%p for i from 0 to s do

%p x:=s-i; y:=i;

%p if not member(x,xx,'p') and

%p not member(y,yy,'p') and

%p not member(x-y,dd,'p') then sw:=1; break; fi;

%p od: # od i

%p if sw=1 then break; fi;

%p od: # od s

%p if sw=-1 then lprint("error, n=",n); break; fi;

%p xx[n]:=x; yy[n]:=y; ss[n]:=x+y; dd[n]:=x-y;

%p od: # od n

%p [seq(xx[i],i=0..M3)]:

%p [seq(yy[i],i=0..M3)]:

%p [seq(ss[i],i=0..M3)]:

%p [seq(dd[i],i=0..M3)]:

%Y Cf A275901, A275902, A276325.

%Y Equals A276324 - 1.

%K nonn

%O 0,2

%A _N. J. A. Sloane_, Oct 03 2016