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%I #9 May 20 2018 10:25:47
%S 10,29,78,100,186,246,380,464,686,798,1096,1276,1658,1878,2408,2668,
%T 3306,3672,4432,4852,5814,6288,7398,8010,9278,9960,11486,12236,13944,
%U 14870,16774,17780,19998,21088,23528,24826,27494,28890,31930,33424,36720,38456
%N Number of -n..n arrays x(0..6) of 7 elements with zero sum and no two consecutive declines, no adjacent equal elements, and no element more than one greater than the previous (random base sawtooth pattern).
%C Row 7 of A200181.
%H R. H. Hardin, <a href="/A200185/b200185.txt">Table of n, a(n) for n = 1..200</a>
%F Empirical: a(n) = -a(n-1) +a(n-3) +2*a(n-4) +2*a(n-5) +2*a(n-6) -2*a(n-8) -3*a(n-9) -3*a(n-10) -2*a(n-11) +2*a(n-13) +2*a(n-14) +2*a(n-15) +a(n-16) -a(n-18) -a(n-19) for n>21.
%F Empirical g.f.: x*(10 + 39*x + 107*x^2 + 168*x^3 + 237*x^4 + 276*x^5 + 292*x^6 + 244*x^7 + 196*x^8 + 128*x^9 + 79*x^10 + 47*x^11 + 40*x^12 + 30*x^13 + 28*x^14 + 22*x^15 + 8*x^16 - 5*x^17 - 12*x^18 - 9*x^19 - x^20) / ((1 - x)^4*(1 + x)^3*(1 - x + x^2)*(1 + x^2)*(1 + x + x^2)^2*(1 + x + x^2 + x^3 + x^4)). - _Colin Barker_, May 20 2018
%e Some solutions for n=6:
%e ..0....3....1....3....6....2....1....2....4....3...-1....3....1....4....4....3
%e ..1....4....2....2...-1....3...-1....3....0....4....0....0...-2....5....5....2
%e ..2....3....0....3....0....4....0...-1....1....5...-1....1...-1...-2....1....3
%e ..3....4....1...-3....1....5....1....0....2...-4....0...-2....0...-1....2...-2
%e .-2...-5...-1...-2...-1...-5....2...-1...-2...-3....1...-1....1...-3...-5...-1
%e .-1...-4....0...-1....0...-4...-2....0...-1...-2....0....0....2...-2...-4....0
%e .-3...-5...-3...-2...-5...-5...-1...-3...-4...-3....1...-1...-1...-1...-3...-5
%Y Cf. A200181.
%K nonn
%O 1,1
%A _R. H. Hardin_, Nov 13 2011
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