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A275902
Following the successive antidiagonals in A275895, let the n-th queen appear in square (x(n),y(n)); sequence gives y(n).
7
0, 2, 1, 4, 3, 8, 5, 10, 7, 6, 12, 14, 9, 18, 11, 13, 21, 24, 15, 26, 17, 16, 28, 30, 19, 20, 34, 36, 22, 38, 23, 40, 25, 27, 44, 47, 29, 31, 50, 52, 32, 33, 55, 57, 35, 37, 59, 62, 39, 65, 41, 42, 69, 43, 71, 73, 45, 75, 46, 77, 49, 48, 81, 83, 51, 85, 53, 88, 54, 56, 91, 58, 95, 97, 60, 99, 61, 101
OFFSET
0,2
COMMENTS
See A275901 for x(n).
This is a permutation of the nonnegative numbers.
This assumes the indexing starts at 0. See A275899, A275900 if the indexing begins at 1.
LINKS
MAPLE
See A275899.
# Alternative Maple program from N. J. A. Sloane, Oct 03 2016
# 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
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Aug 24 2016
STATUS
approved