%I #18 Feb 08 2024 16:46:47
%S 0,1,4,11,25,45,81,121,188,261,368,469,641,785,1000,1220,1520,1767,
%T 2161,2471,2961,3396,3946,4403,5164,5744,6517,7227,8201,8936,10122,
%U 10963,12240,13312,14649,15839,17607,18813,20482,21983,24111,25589,27920,29550,31979
%N Number of kites, distinct up to congruence, on an n X n grid (or geoboard).
%C Only convex kites are counted, not concave kites (sometimes called darts or arrowheads).
%H Lucas A. Brown, <a href="https://github.com/lucasaugustus/oeis/blob/main/A181946.py">Python program</a>.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/Kite.html">Kite</a>.
%e a(1) = 0 because the 1 X 1 grid has no kites.
%e a(2) = 1 because the 2 X 2 grid has one kite.
%e a(3) = 4 because the 3 X 3 grid has 4 congruence classes of kites, out of 10 kites total:
%e +-------+-------+-------+-------+
%e | . . . | o . o | . . o | . o . |
%e | o o . | . . . | o . . | o . o |
%e | o o . | o . o | o o . | . o . |
%e +-------+-------+-------+-------+
%Y Cf. A181944, A189417.
%K nonn
%O 1,3
%A _Martin Renner_, Apr 03 2012
%E a(7)-a(45) from _Lucas A. Brown_, Feb 08 2024
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