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Coordinates Y_lower(n) of P-positions in Maharaja Nim on square spiral (see Comments for precise definition).
5

%I #16 Oct 27 2019 11:16:23

%S 0,1,9,13,19,22,37,52,58,69,78,84,90,101,112,118,132,138,149,160,171,

%T 180,191,200,211,222,228,237,248,259,268,279,288,299,308,319,325,336,

%U 345,356,362,373,382,393,402,413,424,430,441,450,461,470,481,487,498

%N Coordinates Y_lower(n) of P-positions in Maharaja Nim on square spiral (see Comments for precise definition).

%C We study Maharaja Nim on the square spiral, as in A307282, A307283, and in particular the P-positions in the 4th quadrant. As in A140100 and A140101 (which are the analogs if we use a Queen instead of a Maharaja) we take the X-axis to point South and the Y-axis to point East.

%C The P-positions now lie on two roughly straight lines, with coordinates (X_upper(n), Y_upper(n)) with X_upper(n) <= Y_upper(n), and (X_lower(n), Y_lower(n)) with X_lower(n) <= Y_lower(n). These four sequences are A307284-A307287.

%C The two lines are the hard-to-see black pixels in the fourth quadrant in the Sigrist illustration.

%H Rémy Sigrist, <a href="/A307287/b307287.txt">Table of n, a(n) for n = 0..58</a>

%H Rémy Sigrist, <a href="/A307282/a307282_1.png">Colored representation of the spiral for x = -500..500 and y = -500..500</a> (where the hue is function of T(x,y) and black pixels correspond to 0's)

%Y Cf. A140100, A140101, A307282, A307283, A307284-A307287.

%K nonn

%O 0,3

%A _N. J. A. Sloane_, Apr 08 2019

%E More terms from _Rémy Sigrist_, Apr 09 2019