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A275897
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Read the infinite chessboard underlying A065188 by successive antidiagonals and record when the queens are encountered. Here the rows and columns are indexed starting at 0 (as in A275895).
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4
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0, 7, 13, 23, 32, 96, 114, 142, 163, 183, 197, 261, 290, 446, 484, 581, 608, 795, 845, 919, 972, 1018, 1052, 1194, 1255, 1464, 1561, 1733, 1807, 1914, 1992, 2104, 2320, 2387, 2583, 2955, 3051, 3289, 3352, 3602, 3708, 3971, 4039, 4313, 4429, 4522, 4596, 5088, 5316, 5605, 5844, 6173, 6371
(list;
graph;
refs;
listen;
history;
text;
internal format)
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OFFSET
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1,2
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LINKS
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EXAMPLE
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The second queen appears in the fourth antidiagonal at position 7 (calling the top left square square 0):
Qxxx
xxxQ
xQxx
xxxx
so a(2) = 7.
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MAPLE
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# Let b8 be a list of the terms of A065188.
ts:=[];
for n from 1 to 130 do
ta:=b8[n];
tb:=n-1+(ta+n-2)*(ta+n-1)/2;
ts:=[op(ts), tb]; od:
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MATHEMATICA
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b8 = Cases[Import["https://oeis.org/A065188/b065188.txt", "Table"], {_, _}][[All, 2]];
ts = {};
For[n = 1, n <= 130, n++, ta = b8[[n]]; tb = n - 1 + (ta + n - 2)*(ta + n - 1)/2; ts = Append[ts, tb]];
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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