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%I #7 Mar 31 2012 12:36:12
%S 980,2128,4238,7836,13694,22786,36454,56314,84496,123512,176534,
%T 247236,340148,460412,614240,808614,1051792,1352972,1722892,2173378,
%U 2718084,3371956,4152034,5076868,6167438,7446422,8939282,10673432,12679398
%N Number of nondecreasing arrangements of 7 nonzero numbers in -(n+5)..(n+5) with sum zero
%C Row 7 of A188333
%H R. H. Hardin, <a href="/A188337/b188337.txt">Table of n, a(n) for n = 1..200</a>
%F Empirical: a(n)=2*a(n-1)-a(n-3)-a(n-5)+a(n-6)-2*a(n-7)+2*a(n-8)+a(n-9)-a(n-13)-2*a(n-14)+2*a(n-15)-a(n-16)+a(n-17)+a(n-19)-2*a(n-21)+a(n-22).
%F Empirical: G.f. -2*x*(490 +84*x -9*x^2 +170*x^3 +75*x^4 +308*x^5 -67*x^6 +585*x^7 +274*x^8 +36*x^9 -8*x^10 -95*x^11 -302*x^12 -273*x^13 +345*x^14 -126*x^15 +216*x^16 +63*x^17 +165*x^18 -120*x^19 -327*x^20 +198*x^21) / ( (x^2-x+1) *(x^4+x^3+x^2+x+1) *(x^2+1) *(1+x+x^2)^2 *(1+x)^3 *(x-1)^7 ). - R. J. Mathar, Mar 28 2011
%e Some solutions for n=6
%e .-9..-11..-11..-10...-8..-11...-9..-10..-10..-10..-11..-10..-10...-6..-11...-7
%e .-3...-4...-9..-10...-8...-6...-9...-9..-10...-5...-5...-5...-5...-5..-10...-7
%e .-3...-4...-4...-8...-1...-3...-8...-4...-3...-5...-5...-1...-5...-4...-7...-7
%e .-3...-1....2....3....1....1....3....2....3....2...-1....2....2...-1....4....2
%e ..4....3....6....7....1....5....6....5....3....4....7....3....4....4....6....4
%e ..4....7....7....9....6....6....6....8....7....7....7....5....5....5....9....6
%e .10...10....9....9....9....8...11....8...10....7....8....6....9....7....9....9
%K nonn
%O 1,1
%A _R. H. Hardin_ Mar 28 2011
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