A395349 - OEIS

A395349

Consider the square spiral with its cells numbered starting at 0, as in A308884 and A274641. Two players, Black and Red, take turns. When it is Black's turn, he places a queen at the smallest unoccupied cell not attacked by an existing Red queen, and when it is Red's turn, she places a queen at the smallest unoccupied cell not attacked by an existing Black queen. Sequence lists squares occupied by a Red queen.

9, 15, 21, 31, 47, 61, 75, 93, 117, 139, 161, 187, 219, 249, 279, 313, 353, 391, 429, 471, 519, 565, 611, 661, 717, 771, 825, 883, 947, 1009, 1071, 1137, 1209, 1279, 1349, 1423, 1503, 1581, 1659, 1741, 1829, 1915, 2001, 2091, 2187, 2281, 2375, 2473, 2577, 2679, 2781

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,1

COMMENTS

Similar to A392177 and A392178, but placing queens instead of knights.

LINKS

Michael S. Branicky, Table of n, a(n) for n = 0..19999

Michael S. Branicky, Python program for OEIS A395348 and A395349

CROSSREFS

Cf. A395348 (Black queens). See also A308884, A274641, A392177, A392178 (knights).

For queens of a single color, see A273059.

Sequence in context: A225513 A331662 A007962 * A061254 A175626 A391253