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%I #7 Feb 05 2018 09:36:22
%S 21,160,712,2285,5921,13216,26440,48657,83845,137016,214336,323245,
%T 472577,672680,935536,1274881,1706325,2247472,2918040,3739981,4737601,
%U 5937680,7369592,9065425,11060101,13391496,16100560,19231437,22831585
%N Number of length-5 0..n arrays with no following elements larger than the first repeated value.
%C Row 5 of A267471.
%H R. H. Hardin, <a href="/A267473/b267473.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = n^5 + (37/12)*n^4 + (11/2)*n^3 + (77/12)*n^2 + 4*n + 1.
%F Conjectures from _Colin Barker_, Feb 05 2018: (Start)
%F G.f.: x*(21 + 34*x + 67*x^2 - 7*x^3 + 6*x^4 - x^5) / (1 - x)^6.
%F a(n) = 6*a(n-1) - 15*a(n-2) + 20*a(n-3) - 15*a(n-4) + 6*a(n-5) - a(n-6) for n>6.
%F (End)
%e Some solutions for n=7:
%e ..7....1....4....4....7....0....0....7....1....2....4....7....5....6....3....4
%e ..4....0....6....3....7....6....1....2....5....4....4....1....6....1....7....6
%e ..4....1....7....1....7....3....7....4....1....5....2....4....1....4....7....3
%e ..0....3....4....7....1....2....0....1....2....2....1....7....3....7....3....5
%e ..2....6....4....5....5....7....3....1....4....5....4....2....7....7....5....5
%Y Cf. A267471.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 15 2016
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