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 A276783 a(n) = A275901(n) + A275902(n). 5
 0, 3, 4, 6, 7, 13, 14, 16, 17, 18, 19, 22, 23, 29, 30, 33, 34, 39, 40, 42, 43, 44, 45, 48, 49, 53, 55, 58, 59, 61, 62, 64, 67, 68, 71, 76, 77, 80, 81, 84, 85, 88, 89, 92, 93, 94, 95, 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 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS Specifies which diagonals the queens in A275901 and A275902 lie on. LINKS MAPLE # To get 10000 terms of A275902 (xx), A275901 (yy), A276783 (ss), -A276325 (dd) M1:=100000; M2:=22000; M3:=10000; xx:=Array(0..M1, 0); yy:=Array(0..M1, 0); ss:=Array(0..M1, 0); dd:=Array(0..M1, 0); xx[0]:=0; yy[0]:=0; ss[0]:=0; dd[0]:=0; for n from 1 to M2 do sw:=-1;    for s from ss[n-1]+1 to M2 do       for i from 0 to s do          x:=s-i; y:=i;          if not member(x, xx, 'p') and             not member(y, yy, 'p') and             not member(x-y, dd, 'p') then sw:=1; break; fi;       od:  # od i if sw=1 then break; fi;    od: # od s   if sw=-1 then lprint("error, n=", n); break; fi; xx[n]:=x; yy[n]:=y; ss[n]:=x+y; dd[n]:=x-y; od: # od n [seq(xx[i], i=0..M3)]: [seq(yy[i], i=0..M3)]: [seq(ss[i], i=0..M3)]: [seq(dd[i], i=0..M3)]: CROSSREFS Cf A275901, A275902, A276325. Equals A276324 - 1. Sequence in context: A281828 A002982 A290432 * A288731 A093707 A058639 Adjacent sequences:  A276780 A276781 A276782 * A276784 A276785 A276786 KEYWORD nonn AUTHOR N. J. A. Sloane, Oct 03 2016 STATUS approved

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