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A187864 Number of 9-step one space for components leftwards or up, two space for components rightwards or down asymmetric quasi-queen's tours (antidiagonal moves become knight moves) on an n X n board summed over all starting positions.

%I A187864 #9 Jul 22 2025 10:55:53
%S A187864 0,0,414,124880,2090520,9934272,29607932,65963326,123580937,204771252,
%T A187864 310971475,441931786,597915172,777662238,981570648,1208872830,
%U A187864 1459728029,1734003242,2031698469,2352813710,2697348965,3065304234,3456679517
%N A187864 Number of 9-step one space for components leftwards or up, two space for components rightwards or down asymmetric quasi-queen's tours (antidiagonal moves become knight moves) on an n X n board summed over all starting positions.
%C A187864 Row 9 of A187857
%H A187864 R. H. Hardin, <a href="/A187864/b187864.txt">Table of n, a(n) for n = 1..50</a>
%F A187864 Empirical: a(n) = 11710007*n^2 - 135575032*n + 380311550 for n>15
%e A187864 Some solutions for 4X4
%e A187864 ..0..0..4..0....0..5..0..0....0..0..0..0....0..0..2..0....5..4..0..0
%e A187864 ..9..0..6..3....0..4..3..7....0..5..7..6....4..0..1..8....0..3..2..1
%e A187864 ..0..8..5..2....1..0..2..6....2..4..3..9....0..3..0..7....6..8..7..9
%e A187864 ..0..0..7..1....0..0..9..8....1..8..0..0....0..6..5..9....0..0..0..0
%K A187864 nonn
%O A187864 1,3
%A A187864 _R. H. Hardin_ Mar 14 2011