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A250555 Number of length n+2 0..2 arrays with the sum of second differences multiplied by some arrangement of +-1 equal to zero 1

%I #4 Nov 25 2014 09:24:51

%S 5,25,83,297,989,3113,9611,29257,88503,266769,802699,2412545,7246311,

%T 21755889,65301163,195969945,588042095,1764390025,5293696363,

%U 15882140601,47648522543,142949767457,428857697715,1286589881041,3859803210479

%N Number of length n+2 0..2 arrays with the sum of second differences multiplied by some arrangement of +-1 equal to zero

%C Column 2 of A250561

%H R. H. Hardin, <a href="/A250555/b250555.txt">Table of n, a(n) for n = 1..106</a>

%F Empirical: a(n) = 4*a(n-1) +2*a(n-2) -17*a(n-3) -3*a(n-4) +24*a(n-5) +16*a(n-6) -13*a(n-7) -26*a(n-8) +2*a(n-9) +12*a(n-10) for n>15

%e Some solutions for n=6

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

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

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

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_, Nov 25 2014

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Last modified February 20 21:52 EST 2024. Contains 370219 sequences. (Running on oeis4.)