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%I #4 May 05 2013 14:38:18
%S 1,1,3,17,81,397,2073,11291,63121,360909,2102597,12439855,74561687,
%T 451920441,2765717847,17069622035,106139191511,664358517275,
%U 4183117802521,26479526009223,168426949915891,1076002461947039
%N Number of nX6 -1,1 arrays such that the sum over i=1..n,j=1..6 of i*x(i,j) is zero, the sum of x(i,j) is zero, and rows are nondecreasing (number of ways to distribute 6-across galley oarsmen left-right at n fore-aft positions so that there are no turning moments on the ship)
%C Column 6 of A225345
%H R. H. Hardin, <a href="/A225342/b225342.txt">Table of n, a(n) for n = 1..112</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.-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..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..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.-1.-1.-1..1
%K nonn
%O 1,3
%A _R. H. Hardin_ May 05 2013
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