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%I #4 May 05 2013 14:37:00
%S 1,1,3,9,31,107,395,1525,6095,24893,103583,437763,1874497,8116459,
%T 35485099,156453779,694956997,3107415563,13976787615,63201012187,
%U 287163163723,1310481411725,6004334305049,27611237977705,127399143883589
%N Number of nX4 -1,1 arrays such that the sum over i=1..n,j=1..4 of i*x(i,j) is zero, the sum of x(i,j) is zero, and rows are nondecreasing (number of ways to distribute 4-across galley oarsmen left-right at n fore-aft positions so that there are no turning moments on the ship)
%C Column 4 of A225345
%H R. H. Hardin, <a href="/A225340/b225340.txt">Table of n, a(n) for n = 1..135</a>
%e Some solutions for n=4
%e .-1..1..1..1....1..1..1..1...-1.-1.-1.-1...-1.-1..1..1...-1..1..1..1
%e .-1.-1.-1.-1...-1.-1.-1.-1....1..1..1..1...-1.-1..1..1...-1.-1.-1..1
%e .-1..1..1..1...-1.-1.-1.-1....1..1..1..1...-1.-1..1..1...-1.-1.-1..1
%e .-1.-1..1..1....1..1..1..1...-1.-1.-1.-1...-1.-1..1..1...-1..1..1..1
%K nonn
%O 1,3
%A _R. H. Hardin_ May 05 2013