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Number of length n+2 0..4 arrays with the medians of every three consecutive terms nondecreasing
1

%I #4 Nov 13 2014 10:10:26

%S 125,485,1827,6902,24125,81664,274901,899306,2878124,9128858,28568459,

%T 88203357,270034170,819921694,2468386488,7381269147,21942189228,

%U 64848568804,190676777475,558132331487,1626778221234,4723078209157

%N Number of length n+2 0..4 arrays with the medians of every three consecutive terms nondecreasing

%C Column 4 of A250140

%H R. H. Hardin, <a href="/A250136/b250136.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 5*a(n-1) -10*a(n-2) +50*a(n-3) -155*a(n-4) +211*a(n-5) -786*a(n-6) +1706*a(n-7) -1383*a(n-8) +6007*a(n-9) -8058*a(n-10) +2038*a(n-11) -26882*a(n-12) +10262*a(n-13) +7248*a(n-14) +73688*a(n-15) +44407*a(n-16) -5079*a(n-17) -105040*a(n-18) -155452*a(n-19) -62796*a(n-20) +55668*a(n-21) +163440*a(n-22) +121104*a(n-23) +15552*a(n-24) -53568*a(n-25) -62208*a(n-26) -20736*a(n-27)

%e Some solutions for n=6

%e ..0....0....0....1....1....0....2....1....3....2....0....0....2....0....2....3

%e ..1....2....0....1....0....2....2....1....0....0....1....4....2....1....3....1

%e ..2....2....4....4....0....0....3....3....0....0....3....0....3....2....0....0

%e ..1....0....1....1....0....3....2....2....3....1....3....1....2....1....2....4

%e ..3....4....1....1....2....4....2....4....2....4....3....3....3....2....2....3

%e ..3....2....0....1....2....1....2....3....2....1....4....2....4....3....4....3

%e ..3....2....1....0....0....3....0....3....2....0....3....2....3....0....1....3

%e ..3....3....2....1....2....4....4....0....1....2....2....0....1....3....3....0

%K nonn

%O 1,1

%A _R. H. Hardin_, Nov 13 2014