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%I #5 Mar 31 2012 12:36:11
%S 1,5,17,81,374,1818,8964,45225,231596,1202495,6313385,33473871,
%T 178991409,964308854,5229780968,28531772394,156491164870,862470267275,
%U 4774186037351,26533145487533,148001670048543,828332995017980
%N Number of nondecreasing arrangements of n numbers in -(n+2)..(n+2) with sum zero and not more than two numbers equal
%C Column 4 of A188236
%H R. H. Hardin, <a href="/A188231/b188231.txt">Table of n, a(n) for n = 1..28</a>
%e Some solutions for n=5
%e .-4...-6...-3...-6...-7...-7...-4...-4...-6...-7...-5...-3...-7...-7...-7...-4
%e .-4...-5...-2...-3...-4...-2...-2...-2...-2...-1...-5...-3...-6...-3...-5...-3
%e .-1....0...-1....1....2...-1...-1...-1....0....0...-4...-1....3...-1....3...-1
%e ..4....4...-1....1....4....5....0....2....4....2....7....1....5....5....3....3
%e ..5....7....7....7....5....5....7....5....4....6....7....6....5....6....6....5
%K nonn
%O 1,2
%A _R. H. Hardin_ Mar 24 2011
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